$ git clone -n https://src.fedoraproject.org/rpms/rust-libblkid-rs.git /var/lib/mock/f42-build-side-1-3581419-46829/root/chroot_tmpdir/scmroot/rust-libblkid-rs
Cloning into '/var/lib/mock/f42-build-side-1-3581419-46829/root/chroot_tmpdir/scmroot/rust-libblkid-rs'...
$ git fetch origin 8f6f4e867cea3039a886914a62469095223cd363:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-libblkid-rs
 * [new ref]         8f6f4e867cea3039a886914a62469095223cd363 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8f6f4e8 Convert to %autorelease and %autochangelog