Repair bug in 8.2's new logic for planning outer joins: we have to allow joins

Repair bug in 8.2's new logic for planning outer joins: we have to allow joins
that overlap an outer join's min_righthand but aren't fully contained in it,
to support joining within the RHS after having performed an outer join that
can commute with this one.  Aside from the direct fix in make_join_rel(),
fix has_join_restriction() and GEQO's desirable_join() to consider this
possibility.  Per report from Ian Harding.