$ git clone -n https://src.fedoraproject.org/rpms/system-config-printer.git /var/lib/mock/f40-build-804027-144416/root/chroot_tmpdir/scmroot/system-config-printer
Cloning into '/var/lib/mock/f40-build-804027-144416/root/chroot_tmpdir/scmroot/system-config-printer'...
$ git fetch origin 7f845966206a22ba3f3e21711039b3f1dffc9b90:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/system-config-printer
 * [new ref]         7f845966206a22ba3f3e21711039b3f1dffc9b90 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7f84596 fix possible udev service failure if USB device is already handled