$ git clone -n https://src.fedoraproject.org/rpms/gstreamer1-plugins-ugly-free.git /var/lib/mock/f41-build-850698-165573/root/chroot_tmpdir/scmroot/gstreamer1-plugins-ugly-free
Cloning into '/var/lib/mock/f41-build-850698-165573/root/chroot_tmpdir/scmroot/gstreamer1-plugins-ugly-free'...
$ git fetch origin 615db2816d1e9c494d9d1c678f85c5e9fa0f4835:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gstreamer1-plugins-ugly-free
 * [new ref]         615db2816d1e9c494d9d1c678f85c5e9fa0f4835 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 615db28 1.24.8