Fix entirely broken permissions test in new alter_operator regression test.

Not only did this test fail to test what it was supposed to test, but it
left a user definition lying around, which caused subsequent runs of the
regression tests to fail.

Author: tglsfdc

src/test/regress/expected/alter_operator.out

@@ -66,11 +66,10 @@ ERROR:  operator attribute "negator" can not be changed
 -- Test permission check. Must be owner to ALTER OPERATOR.
 --
 CREATE USER regtest_alter_user;
-SET SESSION AUTHORIZATION regtest_alter_user_user;
-ERROR:  role "regtest_alter_user_user" does not exist
+SET SESSION AUTHORIZATION regtest_alter_user;
 ALTER OPERATOR === (boolean, boolean) SET (RESTRICT = NONE);
-RESET SESSION AUTHORIZATION;
+ERROR:  must be owner of operator ===
 -- Clean up
-DROP USER regression_alter_user;
-ERROR:  role "regression_alter_user" does not exist
+RESET SESSION AUTHORIZATION;
+DROP USER regtest_alter_user;
 DROP OPERATOR === (boolean, boolean);

src/test/regress/sql/alter_operator.sql

@@ -48,17 +48,15 @@ ALTER OPERATOR === (boolean, boolean) SET (JOIN = non_existent_func);
 ALTER OPERATOR === (boolean, boolean) SET (COMMUTATOR = !==);
 ALTER OPERATOR === (boolean, boolean) SET (NEGATOR = !==);
 
-
 --
 -- Test permission check. Must be owner to ALTER OPERATOR.
 --
 CREATE USER regtest_alter_user;
-SET SESSION AUTHORIZATION regtest_alter_user_user;
+SET SESSION AUTHORIZATION regtest_alter_user;
 
 ALTER OPERATOR === (boolean, boolean) SET (RESTRICT = NONE);
 
-RESET SESSION AUTHORIZATION;
-
 -- Clean up
-DROP USER regression_alter_user;
+RESET SESSION AUTHORIZATION;
+DROP USER regtest_alter_user;
 DROP OPERATOR === (boolean, boolean);