Mark pg_stat_get_subscription_stats() strict.

It accidentally was marked as non-strict. As it was introduced only in HEAD,
we can just fix the catalog.

Bumps catversion.

Discussion: https://postgr.es/m/20220326212432.s5n2maw6kugnpyxw@alap3.anarazel.de

src/include/catalog/catversion.h

@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202203271
+#define CATALOG_VERSION_NO	202203272
 
 #endif

src/include/catalog/pg_proc.dat

@@ -5377,7 +5377,7 @@
   proargnames => '{slot_name,slot_name,spill_txns,spill_count,spill_bytes,stream_txns,stream_count,stream_bytes,total_txns,total_bytes,stats_reset}',
   prosrc => 'pg_stat_get_replication_slot' },
 { oid => '8523', descr => 'statistics: information about subscription stats',
-  proname => 'pg_stat_get_subscription_stats', proisstrict => 'f',
+  proname => 'pg_stat_get_subscription_stats',
   provolatile => 's', proparallel => 'r',
   prorettype => 'record', proargtypes => 'oid',
   proallargtypes => '{oid,oid,int8,int8,timestamptz}',

src/test/regress/expected/stats.out

@@ -262,4 +262,10 @@ SELECT pg_stat_get_replication_slot(NULL);
  
 (1 row)
 
+SELECT pg_stat_get_subscription_stats(NULL);
+ pg_stat_get_subscription_stats 
+--------------------------------
+ 
+(1 row)
+
 -- End of Stats Test

src/test/regress/sql/stats.sql

@@ -231,6 +231,7 @@ DROP FUNCTION wait_for_hot_stats();
 
 -- ensure that stats accessors handle NULL input correctly
 SELECT pg_stat_get_replication_slot(NULL);
+SELECT pg_stat_get_subscription_stats(NULL);
 
 
 -- End of Stats Test