postgres_fdw: Fix test for parameterized foreign scan.

Commit e4106b252 should have updated this test, but did not; back-patch
to all supported branches.

Reviewed by Richard Guo.

Discussion: http://postgr.es/m/CAPmGK15nR0NXLSCKQAcqbZbTzrzd5MozowWnTnGfPkayndF43Q%40mail.gmail.com

contrib/postgres_fdw/expected/postgres_fdw.out

@@ -738,9 +738,9 @@ EXPLAIN (VERBOSE, COSTS OFF)
          Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (($1::integer = "C 1"))
 (8 rows)
 
-SELECT * FROM ft2 a, ft2 b WHERE a.c1 = 47 AND b.c1 = a.c2;
- c1 | c2 |  c3   |              c4              |            c5            | c6 |     c7     | c8  | c1 | c2 |  c3   |              c4              |            c5            | c6 |     c7     | c8  
-----+----+-------+------------------------------+--------------------------+----+------------+-----+----+----+-------+------------------------------+--------------------------+----+------------+-----
+SELECT * FROM "S 1"."T 1" a, ft2 b WHERE a."C 1" = 47 AND b.c1 = a.c2;
+ C 1 | c2 |  c3   |              c4              |            c5            | c6 |     c7     | c8  | c1 | c2 |  c3   |              c4              |            c5            | c6 |     c7     | c8  
+-----+----+-------+------------------------------+--------------------------+----+------------+-----+----+----+-------+------------------------------+--------------------------+----+------------+-----
   47 |  7 | 00047 | Tue Feb 17 00:00:00 1970 PST | Tue Feb 17 00:00:00 1970 | 7  | 7          | foo |  7 |  7 | 00007 | Thu Jan 08 00:00:00 1970 PST | Thu Jan 08 00:00:00 1970 | 7  | 7          | foo
 (1 row)
 

contrib/postgres_fdw/sql/postgres_fdw.sql

@@ -338,7 +338,7 @@ EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c8 = 'foo';  -- can't be
 -- parameterized remote path for foreign table
 EXPLAIN (VERBOSE, COSTS OFF)
   SELECT * FROM "S 1"."T 1" a, ft2 b WHERE a."C 1" = 47 AND b.c1 = a.c2;
-SELECT * FROM ft2 a, ft2 b WHERE a.c1 = 47 AND b.c1 = a.c2;
+SELECT * FROM "S 1"."T 1" a, ft2 b WHERE a."C 1" = 47 AND b.c1 = a.c2;
 
 -- check both safe and unsafe join conditions
 EXPLAIN (VERBOSE, COSTS OFF)