$ git clone -n https://src.fedoraproject.org/rpms/RBTools.git /var/lib/mock/f42-build-3181747-40950/root/chroot_tmpdir/scmroot/RBTools
Cloning into '/var/lib/mock/f42-build-3181747-40950/root/chroot_tmpdir/scmroot/RBTools'...
$ git fetch origin 20cbe862e22fb5f9e9be02d0d54aa67461e1e594:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/RBTools
 * [new ref]         20cbe862e22fb5f9e9be02d0d54aa67461e1e594 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 20cbe86 Rebuilt for https://fedoraproject.org/wiki/Fedora_42_Mass_Rebuild