$ git clone -n https://src.fedoraproject.org/rpms/ninja-build.git /var/lib/mock/f40-build-1135517-20569/root/chroot_tmpdir/scmroot/ninja-build
Cloning into '/var/lib/mock/f40-build-1135517-20569/root/chroot_tmpdir/scmroot/ninja-build'...
$ git fetch origin 1c9b8efd655062829195152b19b9843e5576c568:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ninja-build
 * [new ref]         1c9b8efd655062829195152b19b9843e5576c568 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1c9b8ef Update to 1.12.1