$ git clone -n https://src.fedoraproject.org/rpms/rust-speakersafetyd.git /var/lib/mock/f40-build-739516-109012/root/chroot_tmpdir/scmroot/rust-speakersafetyd
Cloning into '/var/lib/mock/f40-build-739516-109012/root/chroot_tmpdir/scmroot/rust-speakersafetyd'...
$ git fetch origin 9fda52a7c3857ec41566840fe2ba3f464cf620c2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-speakersafetyd
 * [new ref]         9fda52a7c3857ec41566840fe2ba3f464cf620c2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9fda52a Explicitly create blackbox directory