Use has_table_privilege for TRIGGER on PostgreSQL
What does this MR do?
Gitlab::Database::Grant.create_and_execute_trigger? so it uses
has_table_privilege() on PostgreSQL. This was suggested in comment https://gitlab.com/gitlab-org/gitlab-ce/issues/38634#note_53356552.
Does this MR meet the acceptance criteria?
- Changelog entry added, if necessary
- Has been reviewed by Backend
- Has been reviewed by Database
- Conform by the merge request performance guides
- Conform by the style guides
- Squashed related commits together