When trying to run an UPDATE, this query is ran:

```sql
UPDATE `todos`
INNER JOIN `projects` ON `projects`.`id` = `todos`.`project_id`
SET `todos`.`state` = 'done'
WHERE `todos`.`user_id` = 4
  AND (`todos`.`state` IN ('pending'))
  AND (EXISTS
         (SELECT 1
          FROM `project_authorizations`
          WHERE `project_authorizations`.`user_id` = 4
            AND (project_authorizations.project_id = projects.id))
       OR projects.visibility_level IN (10,
                                        20))
  AND `projects`.`id` IN
    (SELECT `todos`.`project_id`
     FROM `todos`
     WHERE `todos`.`user_id` = 4
       AND (`todos`.`state` IN ('pending')))
  AND (`todos`.`state` != 'done')
```

But MySQL does not like the subquery used to filter on
`projects.id IN (SELECT ...`

Because the subquery queries from the same table:

> Error: You can’t specify target table ‘todos’ for update in FROM clause

So as workaround, wrap it in another subquery, where the original
subquery is aliased using the `AS` statement.

Mostly inspired by https://stackoverflow.com/a/43610081/89376

TodoService should not call `.select(&:id)` on todos, because this is
bad performance. So instead use sub-queries, which will result in a
single SQL query to the database.

https://docs.gitlab.com/ee/development/sql.html#plucking-ids

Move API "basic usage" to be more visible

See merge request !13171

Update reply_by_email_postfix_setup.md, included starting courier-authdaemon after installation.

See merge request !13218

fix Jump to next discussion

Closes #35232

See merge request !13076

Make dropdown style on project page consistent

Closes #35778

See merge request !13193

Don't send rejection mails for all auto-generated mails

Closes #28472

See merge request !13254

Ensure we run installation Rake tasks in a clean env in TestEnv

Closes #35859

See merge request !13249

This would be much more accurate. We assume this is an
auto-generated email if such header is provided, and
the value is not "no". It could also be: "auto-generated",
"auto-replied", or other values from extension. It seems
that only "no" could mean that this is sent by a human.

See: https://tools.ietf.org/html/rfc3834

Do not validate CSRF token in API unless needed

Closes #35705

See merge request !13256

Remove test gitaly when older than version file

See merge request !13250

Fly-out dropdown menu in new sidebar

Closes #34026

See merge request !12938

Fix Prometheus application settings help link to point to Prometheus help page

Closes #33921

See merge request !13258

Disable the Rails/Delegate cop

Closes #35869

See merge request !13267

Empty project factory by default

See merge request !13260

See https://gitlab.com/gitlab-org/gitlab-ce/issues/35869 for the
rationale.
Signed-off-by: Rémy Coutable <remy@rymai.me>

Change project FK migration to skip existing FKs

Closes #35243

See merge request !13235

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

If we call `system('rake', 'taks_name')`, `ENV['RUBYOPT']` is set to
`'-rbundler/setup'` but some tasks (e.g. `gitlab:gitaly:install` need
a clean env since they install their own Gem bundle.
Signed-off-by: Rémy Coutable <remy@rymai.me>

Also make it easier to have mailer helper

Add icons to project sidebar

Closes #34027 and #35877

See merge request !13204

Uniquify reserved word usernames on OAuth user creation

See merge request !13244

Synchronous zanata community contribution translation

Closes #35003

See merge request !13242

Show auto-generated avatars in Groups dashboard tree for Groups without avatars

See merge request !13188

Make Delete Merged Branches handle wildcard protected branches correctly

Closes #35592

See merge request !13251

Update milestone docs CE

See merge request !13233

The "Delete Merged Branches" button should filter out protected
branches matching the wildcard patterns.

Closes gitlab-org/gitlab-ce#35592.