Fix concurrrently in typcache_rel_type_cache.sql

All injection points there must be local.  Otherwise it affects parallel
tests.

Reported-by: Andres Freund
Discussion: https://postgr.es/m/b3ybc66l6lhmtzj2n7ypumz5yjz7njc46sddsqshdtstgj74ah%40qgtn6nzokj6a

src/test/modules/typcache/expected/typcache_rel_type_cache.out

@@ -8,6 +8,13 @@
 -- successful type cache invalidation by relation oid.
 --
 CREATE EXTENSION injection_points;
+-- Make all injection points local to this process, for concurrency.
+SELECT injection_points_set_local();
+ injection_points_set_local 
+----------------------------
+ 
+(1 row)
+
 CREATE TABLE t (i int);
 SELECT injection_points_attach('typecache-before-rel-type-cache-insert', 'error');
  injection_points_attach 

src/test/modules/typcache/sql/typcache_rel_type_cache.sql

@@ -10,6 +10,9 @@
 
 CREATE EXTENSION injection_points;
 
+-- Make all injection points local to this process, for concurrency.
+SELECT injection_points_set_local();
+
 CREATE TABLE t (i int);
 SELECT injection_points_attach('typecache-before-rel-type-cache-insert', 'error');
 SELECT '(1)'::t;