For performance reasons we don't automatically add fabricated users to trust level auto-groups. However, when explicitly passing a trust level to the fabricator, in 99% of cases it means that trust level is relevant for the test, and we need the groups.
This change makes it so that when a trust level is explicitly passed to the fabricator, the auto-groups are refreshed. There's no longer a need to also pass refresh_auto_groups: true, which means clearer tests, fewer mistakes, and less confusion.