$ git clone -n https://src.fedoraproject.org/rpms/libcomps.git /var/lib/mock/f39-build-1515261-35649/root/chroot_tmpdir/scmroot/libcomps
Cloning into '/var/lib/mock/f39-build-1515261-35649/root/chroot_tmpdir/scmroot/libcomps'...
$ git fetch origin 376648717381642f5551b05a921f37f68318b8a0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libcomps
 * [new ref]         376648717381642f5551b05a921f37f68318b8a0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3766487 Update to 0.1.20