$ git clone -n https://src.fedoraproject.org/rpms/rust-tiny-dfr.git /var/lib/mock/f39-build-2459859-61441/root/chroot_tmpdir/scmroot/rust-tiny-dfr
Cloning into '/var/lib/mock/f39-build-2459859-61441/root/chroot_tmpdir/scmroot/rust-tiny-dfr'...
$ git fetch origin 09ba5ac50b40d0975f035c97e2f80e0ef4b4ef6d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-tiny-dfr
 * [new ref]         09ba5ac50b40d0975f035c97e2f80e0ef4b4ef6d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 09ba5ac Update ExcludeArch