The result of NULL not in an unempty set is false. The result of
NULL not in an empty set is true. But if an unempty set has
partitioned locus. This set will be divided into several subsets.
Some subsets may be empty. Because NULL not in empty set equals
true. There will be some tuples that shouldn't exist in the result
set.

The patch disable the partitioned locus of inner table by removing
the join clause from the redistribution_clauses.

this commit cherry pick from 6X_STABLE 8c93db54f3d93a890493f6a6d532f841779a9188
Co-authored-by: NHubert Zhang <hubertzhang@apache.org>
Co-authored-by: NRichard Guo <riguo@pivotal.io>