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 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.