$ git clone -n https://src.fedoraproject.org/rpms/dnf5.git /var/lib/mock/f38-build-709213-92806/root/chroot_tmpdir/scmroot/dnf5
Cloning into '/var/lib/mock/f38-build-709213-92806/root/chroot_tmpdir/scmroot/dnf5'...
$ git fetch origin 6bccf383e56872b9db38bc250a3ab1d009534e05:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/dnf5
 * [new ref]         6bccf383e56872b9db38bc250a3ab1d009534e05 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6bccf38 Default tests off (temporarily, hopefully) on riscv64 arch.