$ git clone -n https://src.fedoraproject.org/rpms/vnstat.git /var/lib/mock/f39-build-1576159-37942/root/chroot_tmpdir/scmroot/vnstat
Cloning into '/var/lib/mock/f39-build-1576159-37942/root/chroot_tmpdir/scmroot/vnstat'...
$ git fetch origin a904a80639d49ab3cfa08b4ca40a4bf638961209:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vnstat
 * [new ref]         a904a80639d49ab3cfa08b4ca40a4bf638961209 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a904a80 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild