$ git clone -n https://src.fedoraproject.org/rpms/gst123.git /var/lib/mock/f39-build-1520021-35825/root/chroot_tmpdir/scmroot/gst123
Cloning into '/var/lib/mock/f39-build-1520021-35825/root/chroot_tmpdir/scmroot/gst123'...
$ git fetch origin a51a84b51da391f4d06dad95c081eac3dcce149d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gst123
 * [new ref]         a51a84b51da391f4d06dad95c081eac3dcce149d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a51a84b Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild