Backfill tests for indexing command dispatch

`projectile-get-ext-command' had no direct test coverage, so the
non-git VCS branches (hg/svn/bzr/darcs/fossil/pijul/sapling/jj) were
relying on indirect coverage that didn't actually exercise the
dispatch. Add a `describe' block that pins each branch.

Also extend the `projectile-dir-files-alien' tests with two cases
that were previously uncovered: the fd path for git (verifying we
don't also call `projectile-git-deleted-files') and the no-VCS
fallback (verifying the generic command is used).

0 files changed, 0 insertions, 0 deletions