$ git clone -n https://src.fedoraproject.org/rpms/snapshot.git /var/lib/mock/f41-build-860706-169155/root/chroot_tmpdir/scmroot/snapshot
Cloning into '/var/lib/mock/f41-build-860706-169155/root/chroot_tmpdir/scmroot/snapshot'...
$ git fetch origin a1cd7354dc2b5a109e2202aee8cf28efb59539d0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/snapshot
 * [new ref]         a1cd7354dc2b5a109e2202aee8cf28efb59539d0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a1cd735 Update to 47.1