$ git clone -n https://src.fedoraproject.org/rpms/gnatcoll.git /var/lib/mock/f40-build-802183-143954/root/chroot_tmpdir/scmroot/gnatcoll
Cloning into '/var/lib/mock/f40-build-802183-143954/root/chroot_tmpdir/scmroot/gnatcoll'...
$ git fetch origin bd74dfcb4959aae0a9c56934872b12f5d1f8dae7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnatcoll
 * [new ref]         bd74dfcb4959aae0a9c56934872b12f5d1f8dae7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bd74dfc Rebuilt with LibGPR 24.