Only recover orphaned collection idents when starting with repair, not after an unclean shutdown

SERVER-35696 made it possible to recover idents with no matching catalog entry as "orphans" in a special namespace, "local.system.orphan-collection-****. This change unintentionally used this behavior when starting from unclean shutdowns, not just when using --repair.

This means that in tests that do many rollbacks, hundreds of collections are created in the "local" database unnecessarily in routine, expected scenarios.

This code should be changed to include only _options.forRepair, not loadingFromUncleanShutdownOrRepair.