repair: drop unnecessary phase cache invalidation After stripping the revlogs, we have been invalidating the phase cache since bf7b8157c483. Later, in 8e3021fd1a44, I added a call to phasecache.filterunknown(). I apparently didn't realize it then, but I now think that that call made the existing phasecache.invalidate() call unnecessary, so this patch drops it. Both the test added in bf7b8157c483 and the entire evolve extension test suite indeed still pass. Differential Revision: https://phab.mercurial-scm.org/D1864