$ git clone -n https://src.fedoraproject.org/rpms/ksirk.git /var/lib/mock/f40-build-2096484-50409/root/chroot_tmpdir/scmroot/ksirk
Cloning into '/var/lib/mock/f40-build-2096484-50409/root/chroot_tmpdir/scmroot/ksirk'...
$ git fetch origin 97f72a80308d35fefafb7f17a4013ceac7d44be3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ksirk
 * [new ref]         97f72a80308d35fefafb7f17a4013ceac7d44be3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 97f72a8 Update sources file