- While deleting a user, some of the user's associated records are moved to the
  ghost user so they aren't deleted. The user is blocked before these records
  are moved, to prevent the user from creating new records while the migration
  is happening, and so preventing a data race.

- Previously, if the migration failed, the user would _remain_ blocked, which is
  not the expected behavior. On the other hand, we can't just stick the block +
  migration into a transaction, because we want the block to be committed before
  the migration starts (for the data race reason mentioned above).

- One solution (implemented in this commit) is to block the user in a parent
  transaction, migrate the associated records in a nested sub-transaction, and
  then unblock the user in the parent transaction if the sub-transaction fails.

Update CI templates to include 9.1 templates

See merge request !10807

Add parameter limit to styleguide

See merge request !10830

Don't run the downtime check on stable branches, or tags/master

See merge request !10794

Kubernetes service namespace

Closes #30445

See merge request !10821

Milestones documentation refactor

See merge request !10812

Adds documentation entry: Don't user forEach, aim for code without side effects

See merge request !10811

Update move icon to match others

Closes #31116

See merge request !10790

Changed milestone.to_reference calls into milestone.title for the show, edit and top views

See merge request !10637

Docs tech articles filetree

Closes #30946

See merge request !10752

Refactor code that creates and destroys project/group members

See merge request !10735

Add email receiver metrics

See merge request !10814

Issue Title Show Focus Check On Load

See merge request !10800

Unassign all Issues and Merge Requests when member leaves a team

Closes #30768 and #24117

See merge request !10755

Update plantuml.md to fix wrong introduced in link.

Closes #31154

See merge request !10806

Refactor into .vue files

See merge request !10788

Add documentation for inactive users in the User cohort

Closes #31195

See merge request !10809

Adds vue js example application and documentation

Closes #30031 and #30030

See merge request !10693

Add ES lint support to identify poorly written Promises

See merge request !9969

Port of fix/29125-ee to CE

Closes #29125

See merge request !10796

This lets us track how many incoming emails a GitLab instance is processing, by
email type (handler) and by project (where applicable).

Do not append issuable state to links with custom anchor

Closes #30916

See merge request !10782

Refactor into .vue files part 2

See merge request !10791