Improve update_all when FROM is a subquery

What does this MR do?

After working in !46260 (merged), we have learned that the UPDATE statement was incorrect because the SQL code doesn't include the subquery.

This change partially reverts the changes in c2b330dc.

This is not a bug because:

• If a project has an issue tracker integration or an external wiki integration, has_external_issue_tracker/has_external_wiki is already true, so we just were updating it again with true. This commit avoids this scenario.
• If a project doesn't have an issue tracker integration or an external wiki integration, has_external_issue_tracker/has_external_wiki is false, so we update it to true.

Example

Having the following database records, we have to create a Jira service on each project belonging to group 1 without the integration and we also have to update the has_external_issue_tracker = true.

Project id: 1, has_external_issue_tracker: false, jira_service_id: nil, group: 1
Project id: 2, has_external_issue_tracker: true, jira_service_id: 1, group: 1
Project id: 3, has_external_issue_tracker: false, jira_service_id: nil, group: 2
Project id: 4, has_external_issue_tracker: false, jira_service_id: nil, group 1

If the UPDATE statement doesn't include the subquery filtering by group:

Project
  .where(id: Project.minimum(:id)..Project.maximum(:id))
  .without_integration(integration)
  .in_namespace(integration.group.self_and_descendants)

It's possible to update all the projects, setting has_external_issue_tracker = true where it should not be updated for project 3.

Related to #268133 (closed)