$ git clone -n https://src.fedoraproject.org/rpms/nanovna-saver.git /var/lib/mock/f39-build-1647030-40430/root/chroot_tmpdir/scmroot/nanovna-saver
Cloning into '/var/lib/mock/f39-build-1647030-40430/root/chroot_tmpdir/scmroot/nanovna-saver'...
$ git fetch origin 131a93ad2939c67bac84b8912918d390dbaff7e5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/nanovna-saver
 * [new ref]         131a93ad2939c67bac84b8912918d390dbaff7e5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 131a93a New version