$ git clone -n https://src.fedoraproject.org/rpms/jack-keyboard.git /var/lib/mock/f41-build-786000-13590/root/chroot_tmpdir/scmroot/jack-keyboard
Cloning into '/var/lib/mock/f41-build-786000-13590/root/chroot_tmpdir/scmroot/jack-keyboard'...
$ git fetch origin 12497509c0629c5cfda664340740986118ad5d4f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jack-keyboard
 * [new ref]         12497509c0629c5cfda664340740986118ad5d4f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1249750 Eliminate use of obsolete %patchN syntax (#2283636)