Fix failed LDAP logins when nil user_id present

Closes #56734

See merge request gitlab-org/gitlab-ce!24749

Resolve "Pipeline stages job action button icon is not aligned"

Closes #56379

See merge request gitlab-org/gitlab-ce!24577

Resolve "Redesign group overview UI: MVC"

Closes #53104

See merge request gitlab-org/gitlab-ce!23866

Convert noteable_discussion_spec.js to Vue test utils

See merge request gitlab-org/gitlab-ce!24765

Quarantine auto devops QA tests

See merge request gitlab-org/gitlab-ce!24786

Added missing parameter cluster_id in the params list for edit project cluster endpoint

See merge request gitlab-org/gitlab-ce!24731

Docs: Minor fix to formatting

See merge request gitlab-org/gitlab-ce!24696

Add script to remove all subgroups within a provided group

See merge request gitlab-org/gitlab-ce!24593

Revert the "What's new" feature

See merge request gitlab-org/gitlab-ce!24772

Overrides commonName Helm chart value

Closes #55820

See merge request gitlab-org/gitlab-ce!24683

When a LDAP user signs in the for the first time and if there
is an `Identity` object with `user_id` of `nil`, new users
will not be able to be register until that entry is cleared
because of the way identities are created:

1. First, the User object is built but not saved, so it has no `id`.
2. Then, `user.identities.build(provider: 'ldapmain')` is called,
   but it does not have an associated `user_id` as a result.
3. `User#save` is called, but the `Identity` validation fails if an
   existing entry with `user_id` of `nil` already exists.

The uniqueness validation for `nil` values doesn't make any sense in
this case. We should be enforcing this at the database level with a
foreign key constraint. To work around the issue we can validate
against the user instead, which does the right thing even when
the user isn't saved yet.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/56734

Port EE style for lib/gitlab/metrics/influx_db.rb

Closes gitlab-ee#6526

See merge request gitlab-org/gitlab-ce!24773

Reduce amount of locks needed for GitHub importer

Closes #54270 and #51817

See merge request gitlab-org/gitlab-ce!24102

Add GitLab Pages predefined variables

See merge request gitlab-org/gitlab-ce!24504

Backport button style changes to CE

See merge request gitlab-org/gitlab-ce!24609

Fix typo: Prometheus Metrics

See merge request gitlab-org/gitlab-ce!24344

Removes duplicated cluster show partials

See merge request gitlab-org/gitlab-ce!24654

Quarantine diff patch spec

See merge request gitlab-org/gitlab-ce!24769

After the import has finished, we flush (delete) the InternalId records
related to the project at hand. This means we're starting over with
tracking correct internal id values, a new record will be created
automatically when the next internal id is generated.

The GitHub importer assigns iid values by using supplied values from
GitHub. We skip tracking internal id values during the import in favor
of higher concurrency. Deleting any InternalId records after the import
has finished is an extra measure to guarantee consistency.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/54270.

This reverts commit fb98496f.

This reverts commit b78a69b0.

This reverts commit 358675d0.

See: https://gitlab.com/gitlab-org/quality/nightly/issues/42
Also failing in staging until the fix is picked into the next release:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/24533

Externalize strings from `/app/views/projects/milestones`

See merge request gitlab-org/gitlab-ce!24726

Signed-off-by: Takuya Noguchi <takninnovationresearch@gmail.com>

Update dependency @gitlab/svgs to ^1.48.0

See merge request gitlab-org/gitlab-ce!24744

Save sorting preference for Issues/MRs in BE

Closes #50352

See merge request gitlab-org/gitlab-ce!24198

Externalize strings from `/app/views/clusters`

See merge request gitlab-org/gitlab-ce!24666

Document how to format localized dates in Ruby

Closes #41237

See merge request gitlab-org/gitlab-ce!24585