Fix consul cleanup removes service files

What does this MR do?

The cleanup of excess consul watcher configs/scripts (introduced in !6747 (merged)) mistakenly touched service configurations as well. The cleanup now filters the available files, to only touch the desired watchers and scripts.

Related issues

Fixes #7717 (closed)

Relates !6747 (merged)

Test Plan

1. Deploy GitLab (EE) with the following config:

consul['enable'] = true
consul['watchers'] = %(postgresql)   
consul['services'] = [ 'postgresql' ]
consul['configuration'] = {
  server: true,
  retry_join: %w(127.0.0.1)
}

4. Verify the files in /var/opt/gitlab/consul/config.d/:

• /var/opt/gitlab/consul/config.d/
  • postgresql_service.json => was created
  • watcher_postgresql.json => was created

3. Run gitlab-ctl reload (or restart the container) with the following config:

consul['enable'] = true
consul['watchers'] = %(newpsql)   
consul['internal']['postgresql_service_name'] = 'newpsql'
consul['configuration'] = {
  server: true,
  retry_join: %w(127.0.0.1)
}

4. Verify that:

• /var/opt/gitlab/consul/config.d/
  • watcher_postgresql.json => has been removed
  • postgresql_service.json => was not deleted
  • watcher_newpsql.json => was created

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion

Required

• Merge Request Title, and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com
• Pipeline is green on dev.gitlab.org if the change is touching anything besides documentation or internal cookbooks
• trigger-package has a green pipeline running against latest commit

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA
• Equivalent MR/issue for the GitLab Chart opened