Making the `gettext:updated_check` by completely regenerating the gitlab.pot.

This avoids an issue where `gettext:find` would not pick up on changes
if the file isn't removed first.

Compile often used regexps only once outside of the loop.

This commit improves the performance of large wiki pages with many, many references.

This partially reverts commit 64dfe2cb.

CHANGELOG
improved comments in API code
improved spec description

Stop relying on migrations in the CacheableAttributes cache key and cache attributes for 1 minute instead
Signed-off-by: NRémy Coutable <remy@rymai.me>

This reverts merge request !20339

We don't need to know the details of every library involved in these calls; they
will always originate in the GitLab app itself.

Allow Labels::FindOrCreateService to find ancestor group labels
Add authentication check on API endpoint
Update flayignore

This assures that old cache is not used if we change format of
cached data.

This adds Keyset pagination to GraphQL lists. PoC for that is
pipelines on merge requests and projects.

When paginating a list, the base-64 encoded id of the ordering
field (in most cases the primary key) can be passed in the `before` or
`after` GraphQL argument.

I never liked the hacky `customized?` method anyway, so this is cleaner.

Closes #48505