Tweak postgres_fdw regression test so autovacuum doesn't change results.

Autovacuum occurring while the test runs could allow some of the inserts to
go into recycled space, thus changing the output ordering of later queries.
While we could complicate those queries to force sorting of their output
rows, it doesn't seem like that would make the test better in any
meaningful way, and conceivably it could hide unexpected diffs.  Instead,
tweak the affected queries so that the inserted rows aren't updated by the
following UPDATE.  Per buildfarm.

contrib/postgres_fdw/expected/postgres_fdw.out

@@ -1951,21 +1951,21 @@ END;
 $$ LANGUAGE plpgsql;
 CREATE TRIGGER t1_br_insert BEFORE INSERT OR UPDATE
     ON "S 1"."T 1" FOR EACH ROW EXECUTE PROCEDURE "S 1".F_BRTRIG();
-INSERT INTO ft2 (c1,c2,c3) VALUES (1208, 218, 'fff') RETURNING *;
+INSERT INTO ft2 (c1,c2,c3) VALUES (1208, 818, 'fff') RETURNING *;
   c1  | c2  |       c3        | c4 | c5 | c6 |     c7     | c8 
 ------+-----+-----------------+----+----+----+------------+----
- 1208 | 218 | fff_trig_update |    |    |    | ft2        | 
+ 1208 | 818 | fff_trig_update |    |    |    | ft2        | 
 (1 row)
 
-INSERT INTO ft2 (c1,c2,c3,c6) VALUES (1218, 218, 'ggg', '(--;') RETURNING *;
+INSERT INTO ft2 (c1,c2,c3,c6) VALUES (1218, 818, 'ggg', '(--;') RETURNING *;
   c1  | c2  |       c3        | c4 | c5 |  c6  |     c7     | c8 
 ------+-----+-----------------+----+----+------+------------+----
- 1218 | 218 | ggg_trig_update |    |    | (--; | ft2        | 
+ 1218 | 818 | ggg_trig_update |    |    | (--; | ft2        | 
 (1 row)
 
-UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 RETURNING *;
+UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 AND c1 < 1200 RETURNING *;
   c1  | c2  |           c3           |              c4              |            c5            | c6 |     c7     | c8  
-------+-----+-----------------------------+------------------------------+--------------------------+------+------------+-----
+------+-----+------------------------+------------------------------+--------------------------+----+------------+-----
     8 | 608 | 00008_trig_update      | Fri Jan 09 00:00:00 1970 PST | Fri Jan 09 00:00:00 1970 | 8  | 8          | foo
    18 | 608 | 00018_trig_update      | Mon Jan 19 00:00:00 1970 PST | Mon Jan 19 00:00:00 1970 | 8  | 8          | foo
    28 | 608 | 00028_trig_update      | Thu Jan 29 00:00:00 1970 PST | Thu Jan 29 00:00:00 1970 | 8  | 8          | foo
@@ -2068,9 +2068,7 @@ UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 RETURNING *;
   998 | 608 | 00998_trig_update      | Thu Apr 09 00:00:00 1970 PST | Thu Apr 09 00:00:00 1970 | 8  | 8          | foo
  1008 | 708 | 0000800008_trig_update |                              |                          |    | ft2        | 
  1018 | 708 | 0001800018_trig_update |                              |                          |    | ft2        | 
- 1208 | 818 | fff_trig_update_trig_update |                              |                          |      | ft2        | 
- 1218 | 818 | ggg_trig_update_trig_update |                              |                          | (--; | ft2        | 
-(104 rows)
+(102 rows)
 
 -- Test errors thrown on remote side during update
 ALTER TABLE "S 1"."T 1" ADD CONSTRAINT c2positive CHECK (c2 >= 0);

contrib/postgres_fdw/sql/postgres_fdw.sql

@@ -329,9 +329,9 @@ $$ LANGUAGE plpgsql;
 CREATE TRIGGER t1_br_insert BEFORE INSERT OR UPDATE
     ON "S 1"."T 1" FOR EACH ROW EXECUTE PROCEDURE "S 1".F_BRTRIG();
 
-INSERT INTO ft2 (c1,c2,c3) VALUES (1208, 218, 'fff') RETURNING *;
-INSERT INTO ft2 (c1,c2,c3,c6) VALUES (1218, 218, 'ggg', '(--;') RETURNING *;
-UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 RETURNING *;
+INSERT INTO ft2 (c1,c2,c3) VALUES (1208, 818, 'fff') RETURNING *;
+INSERT INTO ft2 (c1,c2,c3,c6) VALUES (1218, 818, 'ggg', '(--;') RETURNING *;
+UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 AND c1 < 1200 RETURNING *;
 
 -- Test errors thrown on remote side during update
 ALTER TABLE "S 1"."T 1" ADD CONSTRAINT c2positive CHECK (c2 >= 0);