Run ProjectDestroyWorker after pending_delete attribute has been committed to DB

If a branch starts with an issue's IID, followed by a hyphen, the
description will be updated to say that is closes the issue. This also
updates the title of the merge request to 'Resolves "$issue-title"', as
long as:
- There is more than one commit in the merge request (if there is only
  one commit, the commit's title will be used as before)
- The issue's IID is valid for the project

Closes #17012

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

Use Rugged's TagCollection#create instead of gitlab-shell's Repository#add_tag for better performance
Signed-off-by: NRémy Coutable <remy@rymai.me>

Closes #15527.
Signed-off-by: NRémy Coutable <remy@rymai.me>

This is a combination of 3 commits.

- Update the bare repositories info/attributes if the default branch is updated
- Check the diff attributes of a file before showing a diff
- Update CHANGELOG

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15577

Fixes #15591.
Signed-off-by: NRémy Coutable <remy@rymai.me>

Closes gitlab-org/gitlab-ee#506

This also verify if milestone belongs to correct project before creating
a new issue.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15439

update changelog

Code is based on Project Webhooks, removing deprecations and without
commits listing.

Issue: https://gitlab.com/gitlab-org/gitlab-ce/issues/12785
Merge Request: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3514

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

This allows us to track how much time is spent in updating the
"pushes_since_gc" column as well as the time needed to obtain the lease.