This allows users to add patches as attachments to merge request
created via email.

When an email to create a merge request is sent, all the attachments
ending in `.patch` will be applied to the branch specified in the
subject of the email. If the branch did not exist, it will be created
from the HEAD of the repository.

When the patches could not be applied, the error message will be
replied to the user.

The patches can have a maximum combined size of 2MB for now.

Add endpoint to update a git submodule reference

Closes #41213

See merge request gitlab-org/gitlab-ce!20949

Allow to configure when to retry builds

Closes gitlab-runner#3515

See merge request gitlab-org/gitlab-ce!21758

Allow to install Knative as cluster application

See merge request gitlab-org/gitlab-ce!22593

Expose {closed,merged}_{at,by} in merge requests API index

Closes #52031

See merge request gitlab-org/gitlab-ce!22806

Show expand all button on merge request diffs

Closes #51737

See merge request gitlab-org/gitlab-ce!22873

Fix environment status in merge request widget

Closes #51120 and #25140

See merge request gitlab-org/gitlab-ce!22799

Remove asset_sync gem and related code

Closes omnibus-gitlab#3872

See merge request gitlab-org/gitlab-ce!22610

Adds option to override commit email

Closes #43521

See merge request gitlab-org/gitlab-ce!22560

Touchup Normalizer implementation

See merge request gitlab-org/gitlab-ce!22872

Rewrite SnippetsFinder to improve performance

Closes #52639

See merge request gitlab-org/gitlab-ce!22606

This new endpoint allow users to update a submodule's reference.

The MR involves adding a new operation RPC operation in gitaly-proto
(see gitlab-org/gitaly-proto!233) and change Gitaly to use this
new version (see gitlab-org/gitaly!936).

See gitlab-org/gitlab-ce!20949

This restores the behaviour of showing the expand all button on diffs
even when only a single file is collapsed.
Previously the button would only show when all files are collapsed.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/51737

Bump Gitaly to 0.129.0

See merge request gitlab-org/gitlab-ce!22868

Enhance performance of counting local Uploads

Closes gitlab-ee#6070

See merge request gitlab-org/gitlab-ce!22522

The private commit email is automatically generated in the format:
id-username@noreply.HOSTNAME

GitLab instance admins are able to change the HOSTNAME portion,
that defaults to Gitlab's hostname, to whatever they prefer.

before:

- Method `validate_retry_max` has a Cognitive Complexity of 9 (exceeds 5 allowed). Consider refactoring.
- Method `validate_retry_when` has a Cognitive Complexity of 6 (exceeds 5 allowed). Consider refactoring.

before:

- Method `validate_retry` has a Cognitive Complexity of 7 (exceeds 5 allowed). Consider refactoring.
- Method `validate_retry_max` has a Cognitive Complexity of 9 (exceeds 5 allowed). Consider refactoring.
- Method `validate_retry_when` has a Cognitive Complexity of 14 (exceeds 5 allowed). Consider refactoring.