Optimize read-only middleware so that it does not consume as much CPU

Closes #40185 and gitlab-com/infrastructure#3240

See merge request gitlab-org/gitlab-ce!15504

Skip confirmation user api

Closes #28934

See merge request gitlab-org/gitlab-ce!15175

Custom issue tracker

See merge request gitlab-org/gitlab-ce!15516

Resolve "Notes API for issues no longer returns label additions/removals"

Closes #39461

See merge request gitlab-org/gitlab-ce!15080

Resolve "TagsPage|Tags"

Closes #40367

See merge request gitlab-org/gitlab-ce!15512

This reverts commit 91075c82.

Batch load blobs for diff generation

Closes #37599

See merge request gitlab-org/gitlab-ce!15370

Fix promoting milestone updating all issuables without milestone

Closes #40337

See merge request gitlab-org/gitlab-ce!15487

After installing a new gem, batch-loader, a construct can be used to
queue data to be fetched in bulk. The gem was also introduced in both
gitlab-org/gitlab-ce!14680 and gitlab-org/gitlab-ce!14846, but those mrs
are not merged yet.

For the generation of diffs, both the old blob and the new blob need to
be loaded. This for every file in the diff, too. Now we collect all
these so we do 1 fetch. Three `.allow_n_plus_1_calls` have been removed,
which I expect to be valid, but this needs to be confirmed by a full CI
run.

Possibly closes:
- https://gitlab.com/gitlab-org/gitlab-ce/issues/37445
- https://gitlab.com/gitlab-org/gitlab-ce/issues/37599
- https://gitlab.com/gitlab-org/gitlab-ce/issues/37431

since `Rails.application.routes.url_helpers` creates a new anonymous module every time it's called

Fix slow gitaly dev test bundle

See merge request gitlab-org/gitlab-ce!15508

Signed-off-by: Rémy Coutable <remy@rymai.me>

Export code as ES6 modules

See merge request gitlab-org/gitlab-ce!15503

Backport ability to enable/disable file attachments in issuable form

See merge request gitlab-org/gitlab-ce!15433

Memoize GitlabShellAdapter for performance and ease of testing

See merge request gitlab-org/gitlab-ce!15507

Fix commits list 500 with multi-file editor new_repo cookie

Closes #39821

See merge request gitlab-org/gitlab-ce!15502

Remove a useless `allow_failure: no` and use `true` instead of `yes`

See merge request gitlab-org/gitlab-ce!15491

Port of https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/3463#note_47990536

Update gRPC to v1.7.2

Closes gitaly#742

See merge request gitlab-org/gitlab-ce!15439

In !15082, we changed the behavior of the middleware to call
`Rails.application.routes.recognize_path` whenever a new route arrived.
However, this can be a CPU-intensive task because Rails needs to allocate
memory and compile 850+ different regular expressions, which are complicated
in GitLab.

As a short-term fix, we can do a lightweight string match before
we do the heavier comparison.

Closes #40185, gitlab-com/infrastructure#3240

Fix https://gitlab.com/gitlab-org/gitlab-ce/issues/39821

/<namespace>/<project>/commmits/master

remove the rake task `gitlab:sidekiq:drop_post_receive`

Closes #40290

See merge request gitlab-org/gitlab-ce!15493

Fix merge_requests.source_project_id migration

See merge request gitlab-org/gitlab-ce!15496

[CE] Impersonation no longer gets stuck on password change.

Closes #13888

See merge request gitlab-org/gitlab-ce!15497

Add inline editing to issues on mobile

Closes #39497

See merge request gitlab-org/gitlab-ce!15438

Align retry button with job title with new grid size

Closes #40342

See merge request gitlab-org/gitlab-ce!15462

Fix bitbucket wiki import with hashed storage enabled

Closes #40292

See merge request gitlab-org/gitlab-ce!15490

improve requirements details

See merge request gitlab-org/gitlab-ce!15265

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