Fix test failure with non-MULTIPLICITY Perl interpreters.

Per buildfarm.

src/pl/plperl/expected/plperl_setup.out

@@ -32,6 +32,9 @@ SELECT foo1();
     1
 (1 row)
 
+-- Must reconnect to avoid failure with non-MULTIPLICITY Perl interpreters
+\c -
+SET ROLE regress_user1;
 -- Should be able to change privileges on the language
 revoke all on language plperl from public;
 SET ROLE regress_user2;

src/pl/plperl/sql/plperl_setup.sql

@@ -31,6 +31,11 @@ CREATE EXTENSION plperlu;  -- fail
 CREATE FUNCTION foo1() returns int language plperl as '1;';
 SELECT foo1();
 
+-- Must reconnect to avoid failure with non-MULTIPLICITY Perl interpreters
+\c -
+
+SET ROLE regress_user1;
+
 -- Should be able to change privileges on the language
 revoke all on language plperl from public;