$ git clone -n https://src.fedoraproject.org/rpms/free42.git /var/lib/mock/f38-build-side-42-init-devel-1168634-30610/root/chroot_tmpdir/scmroot/free42
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1168634-30610/root/chroot_tmpdir/scmroot/free42'...
$ git fetch origin af7ef87f76c5966652397d8ebdc02516709f096b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/free42
 * [new ref]         af7ef87f76c5966652397d8ebdc02516709f096b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at af7ef87 Update to 3.0.21