$ git clone -n https://src.fedoraproject.org/rpms/gstreamer1-plugins-ugly-free.git /var/lib/mock/f40-build-752732-116843/root/chroot_tmpdir/scmroot/gstreamer1-plugins-ugly-free
Cloning into '/var/lib/mock/f40-build-752732-116843/root/chroot_tmpdir/scmroot/gstreamer1-plugins-ugly-free'...
$ git fetch origin 38a225dbfcc3e10357d92c0dc77db42ddd825866:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gstreamer1-plugins-ugly-free
 * [new ref]         38a225dbfcc3e10357d92c0dc77db42ddd825866 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 38a225d 1.22.7