$ git clone -n https://src.fedoraproject.org/rpms/rust-system-deps.git /var/lib/mock/f42-build-side-1-3587399-46931/root/chroot_tmpdir/scmroot/rust-system-deps
Cloning into '/var/lib/mock/f42-build-side-1-3587399-46931/root/chroot_tmpdir/scmroot/rust-system-deps'...
$ git fetch origin 2040f82d8d9e171d02931c44a81aff1bb2062c96:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-system-deps
 * [new ref]         2040f82d8d9e171d02931c44a81aff1bb2062c96 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2040f82 Update to version 7.0.5; Fixes RHBZ#2367467