$ git clone -n https://src.fedoraproject.org/rpms/rust-nu-test-support.git /var/lib/mock/f40-build-2613558-64071/root/chroot_tmpdir/scmroot/rust-nu-test-support
Cloning into '/var/lib/mock/f40-build-2613558-64071/root/chroot_tmpdir/scmroot/rust-nu-test-support'...
$ git fetch origin c4961ec379ecd60bb7a738d7d34752727fd97e87:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-nu-test-support
 * [new ref]         c4961ec379ecd60bb7a738d7d34752727fd97e87 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c4961ec Update to 0.91.0 (rhbz#2257516)