$ git clone -n https://src.fedoraproject.org/rpms/cosmic-greeter.git /var/lib/mock/f41-build-857445-168094/root/chroot_tmpdir/scmroot/cosmic-greeter
Cloning into '/var/lib/mock/f41-build-857445-168094/root/chroot_tmpdir/scmroot/cosmic-greeter'...
$ git fetch origin 7937c7fec2966435f1a9404f74e05d399d40b8d3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cosmic-greeter
 * [new ref]         7937c7fec2966435f1a9404f74e05d399d40b8d3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7937c7f "Update to 1.0.0~alpha.2"