Mark join assoiativity & commutativity GUC visible
Mark join assoiativity & commutativity GUC visible

Allow GUC optimizer_join_arity_for_associativity_commutativity
to be visible to regular database users.

edespino/gpdb,xinzweb/gpdb,greenplum-db/gpdb,xinzweb/gpdb,lisakowen/gpdb,xinzweb/gpdb,yuanzhao/gpdb,adam8157/gpdb,ashwinstar/gpdb,yuanzhao/gpdb,Chibin/gpdb,lisakowen/gpdb,greenplum-db/gpdb,50wu/gpdb,jmcatamney/gpdb,lisakowen/gpdb,edespino/gpdb,ashwinstar/gpdb,ashwinstar/gpdb,Chibin/gpdb,50wu/gpdb,yuanzhao/gpdb,Chibin/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,edespino/gpdb,Chibin/gpdb,adam8157/gpdb,ashwinstar/gpdb,Chibin/gpdb,xinzweb/gpdb,Chibin/gpdb,xinzweb/gpdb,Chibin/gpdb,yuanzhao/gpdb,lisakowen/gpdb,xinzweb/gpdb,edespino/gpdb,lisakowen/gpdb,greenplum-db/gpdb,edespino/gpdb,ashwinstar/gpdb,50wu/gpdb,jmcatamney/gpdb,adam8157/gpdb,edespino/gpdb,yuanzhao/gpdb,yuanzhao/gpdb,greenplum-db/gpdb,edespino/gpdb,50wu/gpdb,jmcatamney/gpdb,jmcatamney/gpdb,yuanzhao/gpdb,xinzweb/gpdb,adam8157/gpdb,adam8157/gpdb,greenplum-db/gpdb,edespino/gpdb,yuanzhao/gpdb,50wu/gpdb,yuanzhao/gpdb,edespino/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,lisakowen/gpdb,jmcatamney/gpdb,Chibin/gpdb,xinzweb/gpdb,Chibin/gpdb,adam8157/gpdb,50wu/gpdb,jmcatamney/gpdb,adam8157/gpdb,edespino/gpdb,greenplum-db/gpdb,50wu/gpdb,50wu/gpdb,lisakowen/gpdb,greenplum-db/gpdb,adam8157/gpdb,yuanzhao/gpdb,Chibin/gpdb,lisakowen/gpdb,ashwinstar/gpdb