$ git clone -n https://src.fedoraproject.org/rpms/prunerepo.git /var/lib/mock/f39-build-1642268-40212/root/chroot_tmpdir/scmroot/prunerepo
Cloning into '/var/lib/mock/f39-build-1642268-40212/root/chroot_tmpdir/scmroot/prunerepo'...
$ git fetch origin 48c186aef353573391deb7f58b52a946d51effc5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/prunerepo
 * [new ref]         48c186aef353573391deb7f58b52a946d51effc5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 48c186a Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild