$ git clone -n https://src.fedoraproject.org/rpms/shim-unsigned-aarch64.git /var/lib/mock/f39-build-2541367-61806/root/chroot_tmpdir/scmroot/shim-unsigned-aarch64
Cloning into '/var/lib/mock/f39-build-2541367-61806/root/chroot_tmpdir/scmroot/shim-unsigned-aarch64'...
$ git fetch origin 80384861d020052ebfad44c37f16ab35f341f770:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/shim-unsigned-aarch64
 * [new ref]         80384861d020052ebfad44c37f16ab35f341f770 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8038486 Update to shim-15.8