$ git clone -n https://src.fedoraproject.org/rpms/rust-os_type.git /var/lib/mock/f41-build-side-1-3134862-39763/root/chroot_tmpdir/scmroot/rust-os_type
Cloning into '/var/lib/mock/f41-build-side-1-3134862-39763/root/chroot_tmpdir/scmroot/rust-os_type'...
$ git fetch origin c53d3c5d6433149373457afb5b426ad005503cfa:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-os_type
 * [new ref]         c53d3c5d6433149373457afb5b426ad005503cfa -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c53d3c5 unused leaf package for more than two release cycles