This commits extract code responsible for calculating essential CI/CD
variables to a separate concern. This makes it possible to share this
code between a `Ci::Build` and a `Ci::Bridge`.

We might want to refactor this to use composition instead of
inheritance.

Removing old code path for search_files_by_content

See merge request gitlab-org/gitlab-ce!25617

Eliminate most N+1 queries loading UserController#calendar_activities

Closes #58392

See merge request gitlab-org/gitlab-ce!25697

In 11.8, we added a fix for the SearchFilesByContent RPC in gitaly to
send back the response in chunks. However, we kept in the old code path
for backwards compatibility. Now that the change is fully deployed, we
can remove that old codepath.

Bump Bootsnap to 1.4.1

See merge request gitlab-org/gitlab-ce!25701

1.4.1 contains a number of bug fixes and performance improvements:
https://github.com/Shopify/bootsnap/blob/master/CHANGELOG.md

Resolve "Github importer ignores Milestone due_date"

Closes #57612

See merge request gitlab-org/gitlab-ce!25182

Fix some 404 links into charts project

See merge request gitlab-org/gitlab-ce!25589

Add quick link to GitLab.com settings

See merge request gitlab-org/gitlab-ce!25580

Add confidential issue linking guidance

See merge request gitlab-org/gitlab-ce!25326

We can reduce a significant number of queries by preloading the
associations for events.

On GitLab.com, for a date that had 456 events, this brought the load
time down from 8.7 to 1.2 s.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/58392

Fix GitLab::JsonCache when reading a persisted entry back from the cache

See merge request gitlab-org/gitlab-ce!25587

Hashed Storage rollback mechanism

See merge request gitlab-org/gitlab-ce!23955

Update Serverless docs with livestream feedback

See merge request gitlab-org/gitlab-ce!25616

Add suffix (`_event`) to merge request source

Closes gitlab-ee#9893

See merge request gitlab-org/gitlab-ce!25508

Minor grammar and accuracy fixes

See merge request gitlab-org/gitlab-ce!25665

Add Sentry project dropdown to error tracking settings form

See merge request gitlab-org/gitlab-ce!24701

- Move some specs into contexts
- Let get_slugs method take a parameter and return a specific slug.
- Add rescues when using Addressable::URI.

`project_migrate_hashed_storage` is now
`hashed_storage:hashed_storage_project_migrate`

Exceptions were also simplified from 2 to 1.

`try_to_set_repository_read_only!` is now on the Base class.
Simplified Exception classes from 2 to 1 with a more descriptive name.

New class contains the ExclusiveLease specifics that is shared among
both the Migration and Rollback workers.

This change takes the case where repository doesn't exist on disk
and make it ignore but succeed the step, increasing or decreasing the
version depending on the operation.

Rollback is done similar to Migration for the Hashed Storage.
It also shares the same ExclusiveLease key to prevent both happening
at the same time.

All Hashed Storage related workers now share the same queue namespace
which allows for assigning dedicated workers easily.

Moved to HashedStorage namespace, and added them to the
`:hashed_storage` queue namespace

We are adding sidekiq workers and service classes to allow to rollback
a hashed storage migration. There are some refactoring involved as well
as part of the code can be reused by both the migration and the rollback
logic.

Moves EE differences out of number_utils.js

Closes gitlab-ee#10097

See merge request gitlab-org/gitlab-ce!25680