Speed up checking for approvers remaining

Closes #1843 and #2448

See merge request !2032

Stop using sidekiq-cron for scheduling all project mirror pull and move to adaptive scheduling

Closes gitlab-ce#29218

See merge request !1853

Implement server-wide Audit Logging admin screen

Closes #2336

See merge request !1852

Resolve "Approvers don't appear when MR is created from a fork"

Closes #2556

See merge request !2035

Remove references to old settings location

See merge request !2043

re-add avatar url to approver avatar

Closes #2560

See merge request !2034

The `users_select_tag` helper defaults to using `@project`, which in this case
is the source project, not the target project. Explicitly use the target project
to get the right list of users.

1. Use the ProjectAuthorization model to find users with developer access to
   this project. This is dramatically faster than the old version, with the
   complicated ORs, on staging: ~10ms vs ~800ms.
2. Use `to_a` explicitly when checking `any?` on a relation. Refactoring out the
   `any?` checks would be painful, but as we often use the results anyway,
   `to_a` lets us save a query.

Adding this up gets us the below (for a MR on the gitlab-ce project in staging).

Before:

    Project Load (2.3ms) SELECT "projects".* FROM "projects" WHERE
    "projects"."pending_delete" = 'f' AND "projects"."id" = 13083 ORDER BY
    "projects"."id" DESC LIMIT 1 [["pending_delete", false], ["id", 13083]]

    Approver Exists (1.2ms) SELECT 1 AS one FROM "approvers" WHERE
    "approvers"."target_id" = 2294769 AND "approvers"."target_type" =
    'MergeRequest' LIMIT 1 [["target_id", 2294769], ["target_type",
    "MergeRequest"]]

    ApproverGroup Exists (0.8ms) SELECT 1 AS one FROM "approver_groups" WHERE
    "approver_groups"."target_id" = 2294769 AND "approver_groups"."target_type"
    = 'MergeRequest' LIMIT 1 [["target_id", 2294769], ["target_type",
    "MergeRequest"]]

    User Load (2.7ms) SELECT "users".* FROM "users" WHERE "users"."id" = 840794
    ORDER BY "users"."id" DESC LIMIT 1 [["id", 840794]]

    Approver Load (0.9ms) SELECT "approvers".* FROM "approvers" WHERE
    "approvers"."target_id" = 13083 AND "approvers"."target_type" = 'Project'
    AND ("approvers"."user_id" != 840794) [["target_id", 13083], ["target_type",
    "Project"], ["user_id", 840794]]

    Approver Exists (0.6ms) SELECT 1 AS one FROM "approvers" WHERE
    "approvers"."target_id" = 2294769 AND "approvers"."target_type" =
    'MergeRequest' LIMIT 1 [["target_id", 2294769], ["target_type",
    "MergeRequest"]]

    ApproverGroup Exists (0.6ms) SELECT 1 AS one FROM "approver_groups" WHERE
    "approver_groups"."target_id" = 2294769 AND "approver_groups"."target_type"
    = 'MergeRequest' LIMIT 1 [["target_id", 2294769], ["target_type",
    "MergeRequest"]]

    ApproverGroup Load (0.7ms) SELECT "approver_groups".* FROM "approver_groups"
    WHERE "approver_groups"."target_id" = 13083 AND
    "approver_groups"."target_type" = 'Project' [["target_id", 13083],
    ["target_type", "Project"]]

    Group Load (1.3ms) SELECT "namespaces".* FROM "namespaces" WHERE
    "namespaces"."deleted_at" IS NULL AND "namespaces"."type" IN ('Group') AND
    "namespaces"."id" = 9970 AND "namespaces"."type" IN ('Group') AND
    "namespaces"."type" = 'Group' ORDER BY "namespaces"."id" DESC LIMIT 1
    [["id", 9970], ["type", "Group"]]

    (1222.4ms) SELECT COUNT(*) FROM "users" WHERE ("users"."state"
    IN ('active')) AND ("users"."ghost" = 'f' OR "users"."ghost" IS NULL)
    AND ("users"."support_bot" = 'f' OR "users"."support_bot" IS NULL) AND ((id
    IN (SELECT "members"."user_id" FROM "members" WHERE "members"."source_type"
    = 'Project' AND "members"."type" IN ('ProjectMember') AND
    "members"."source_id" = 13083 AND "members"."source_type" = 'Project' AND
    "members"."type" IN ('ProjectMember') AND "members"."requested_at" IS NULL
    AND (access_level > 20) ORDER BY "members"."id" DESC) OR id IN (SELECT
    "members"."user_id" FROM "members" WHERE "members"."source_type" =
    'Namespace' AND "members"."type" IN ('GroupMember') AND
    "members"."source_id" = 9970 AND "members"."source_type" = 'Namespace' AND
    "members"."type" IN ('GroupMember') AND "members"."requested_at" IS NULL
    AND (access_level > 20) ORDER BY "members"."id" DESC)) AND id NOT IN (SELECT
    "approvals"."user_id" FROM "approvals" WHERE "approvals"."merge_request_id"
    = 2294769)) AND ("users"."id" != 840794) [["id", 840794]]

After:

    Project Load (2.5ms) SELECT "projects".* FROM "projects" WHERE
    "projects"."pending_delete" = 'f' AND "projects"."id" = 13083 ORDER BY
    "projects"."id" DESC LIMIT 1 [["pending_delete", false], ["id", 13083]]

    Approver Load (1.3ms) SELECT "approvers".* FROM "approvers" WHERE
    "approvers"."target_id" = 2294769 AND "approvers"."target_type" =
    'MergeRequest' [["target_id", 2294769], ["target_type", "MergeRequest"]]

    ApproverGroup Load (1.5ms) SELECT "approver_groups".* FROM "approver_groups"
    WHERE "approver_groups"."target_id" = 2294769 AND
    "approver_groups"."target_type" = 'MergeRequest' [["target_id", 2294769],
    ["target_type", "MergeRequest"]]

    User Load (2.9ms) SELECT "users".* FROM "users" WHERE "users"."id" = 840794
    ORDER BY "users"."id" DESC LIMIT 1 [["id", 840794]]

    Approver Load (0.9ms) SELECT "approvers".* FROM "approvers" WHERE
    "approvers"."target_id" = 13083 AND "approvers"."target_type" = 'Project'
    AND ("approvers"."user_id" != 840794) [["target_id", 13083], ["target_type",
    "Project"], ["user_id", 840794]]

    ApproverGroup Load (0.7ms) SELECT "approver_groups".* FROM "approver_groups"
    WHERE "approver_groups"."target_id" = 13083 AND
    "approver_groups"."target_type" = 'Project' [["target_id", 13083],
    ["target_type", "Project"]]

    (6.2ms) SELECT COUNT(*) FROM "users" WHERE ("users"."state" IN ('active'))
    AND ("users"."ghost" = 'f' OR "users"."ghost" IS NULL)
    AND ("users"."support_bot" = 'f' OR "users"."support_bot" IS NULL) AND ((id
    IN (SELECT "project_authorizations"."user_id" FROM "project_authorizations"
    WHERE (project_id = 13083 AND access_level > 20))) AND id NOT IN (SELECT
    "approvals"."user_id" FROM "approvals" WHERE "approvals"."merge_request_id"
    = 2294769)) AND ("users"."id" != 840794) [["id", 840794]]

Per user/group access levels for Protected Tags

Closes #2132

See merge request !1629

Fix '/unassign' slash command

Closes #2470 and #2516

See merge request !1986

[EE] Enable the Style/PreferredHashMethods cop

See merge request !2023

Merge branch '2532-saving-a-mirrored-project-errors-out-if-mirror-user-has-been-deleted' into 'master'

Update mirror user for all projects deleted user is mirror_user for

Closes #2532

See merge request !2013

Add shared_runners_minutes_limit to groups and users API

See merge request !1942

Geo: use GeoNode#clone_url_prefix for the Geo::RepositorySyncService

See merge request !2028

Forbid Sidekiq scheduling in transactions [EE]

See merge request !2024

Feedback:
https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/1942#note_31511130

Clarify license should be uploaded to the primary Geo node

See merge request !1947

[ci skip]

Scheduling jobs in transactions can lead to race conditions where a job
runs before a transaction has been committed. The added initializer
ensures the various Sidekiq scheduling methods raise an error when
called inside a transaction.

Fixes #27233

made by the API. TODO: Need to do this for CE and all
the API tests as well