Run a consistency check on this VersionStore library.

def _fsck(self, dry_run):
        """
        Run a consistency check on this VersionStore library.
        """
        # Cleanup Orphaned Chunks
        self._cleanup_orphaned_chunks(dry_run)
        # Cleanup unreachable SHAs (forward pointers)
        self._cleanup_unreachable_shas(dry_run)
        # Cleanup Orphaned Snapshots
        self._cleanup_orphaned_versions(dry_run)