Fix pipeline failure
Fix pipeline failure

commit f9435307 access 'Relation' after it's closed.

Co-authored-by: Alexandra Wang <2104ed7b77de63c11d65f08ed993b286192143d2@pivotal.io>
Co-authored-by: Gang Xiong <5614de4ed36375d47b39bf47c8bdae2cb0cd0d22@pivotal.io>

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