git 2.15.0 has some significant performance improvements when running `git
fetch` on a repository that has lots of references. See
https://gitlab.com/gitlab-com/migration/issues/216#note_60672987 for more
details.

Signed-off-by: NRémy Coutable <remy@rymai.me>

Simplify the codequality job

See merge request gitlab-org/gitlab-ee!4602

Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NRémy Coutable <remy@rymai.me>

Branches started from `security-X-Y` will likely fail on `ee_compat_check`,
the check tries to merge against EE `master` which may likely fail for MR that
are not targetted on `master`, like security fixes.

This commit disables `ee_compat_check` on branches starting with `security-`.

The default behavior of seed_fu is to load the fixtures using the RAILS_ENV
environment.  In CI, since we set RAILS_ENV=test, nothing is ever
loaded. Instead of `rake db:seed_fu`, use `rake gitlab:setup`, which sets up
MySQL properly with limits.

Closes #41517

Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NRémy Coutable <remy@rymai.me>

This is a pretty boring solution, but I can't
think of a good idea right now and this might be
good enough for now...

Signed-off-by: NRémy Coutable <remy@rymai.me>

Also, name the remotes in Gitlab::EeCompatCheck
Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NRémy Coutable <remy@rymai.me>

We have run into permission issues with MySQL triggers in #36633 that
would have been caught earlier either if our migration tests or GitLab QA
tests had been testing against non-superuser users. This change creates
a non-superuser that has access to the GitLab test database and uses that.

Closes #39932