$ git clone -n https://src.fedoraproject.org/rpms/ghostscript.git /var/lib/mock/f42-build-side-1-3500922-45971/root/chroot_tmpdir/scmroot/ghostscript
Cloning into '/var/lib/mock/f42-build-side-1-3500922-45971/root/chroot_tmpdir/scmroot/ghostscript'...
$ git fetch origin fc2f006f43a80c8aa1eefdec5a04894d8fdc8bd2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghostscript
 * [new ref]         fc2f006f43a80c8aa1eefdec5a04894d8fdc8bd2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fc2f006 10.05.0 (fedora#2351692)