$ git clone -n https://src.fedoraproject.org/rpms/rust-cargo.git /var/lib/mock/f42-build-3253022-41225/root/chroot_tmpdir/scmroot/rust-cargo
Cloning into '/var/lib/mock/f42-build-3253022-41225/root/chroot_tmpdir/scmroot/rust-cargo'...
$ git fetch origin 36cd39d4f9e7faba0752dd3d03cb202dcbde2264:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cargo
 * [new ref]         36cd39d4f9e7faba0752dd3d03cb202dcbde2264 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 36cd39d Bump gix dependency from 0.66 to 0.70