$ git clone -n https://src.fedoraproject.org/rpms/plasma-oxygen.git /var/lib/mock/f41-build-847803-164127/root/chroot_tmpdir/scmroot/plasma-oxygen
Cloning into '/var/lib/mock/f41-build-847803-164127/root/chroot_tmpdir/scmroot/plasma-oxygen'...
$ git fetch origin 4bd309bc8e419a8f9e241b5e4a086a440762a6e2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-oxygen
 * [new ref]         4bd309bc8e419a8f9e241b5e4a086a440762a6e2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4bd309b 6.1.5