PG-354: pg_stat_monitor: Remove pg_stat_monitor_settings view

Removing the view for 2.0. Updating the required SQL files to manage
the upgrade. Downgrade from 2.x to 1.x is not supported.

Also part of this fix is the SQL regression. This does not update the
tap test cases.

regression/sql/guc.sql

@@ -1,6 +1,31 @@
 CREATE EXTENSION pg_stat_monitor;
-SELECT pg_stat_monitor_reset();
-select pg_sleep(.5);
-SELECT * FROM pg_stat_monitor_settings WHERE name NOT LIKE 'pg_stat_monitor.pgsm_track_planning' ORDER BY name COLLATE "C";
-SELECT pg_stat_monitor_reset();
+
+\x
+
+SELECT  name
+        , setting
+        , unit
+        , category
+        , short_desc
+        , extra_desc
+        , context
+        , vartype
+        , source
+        , min_val
+        , max_val
+        , enumvals
+        , boot_val
+        , reset_val
+        , sourcefile
+        , sourceline
+        , pending_restart 
+FROM    pg_settings
+WHERE   name     LIKE     'pg_stat_monitor.%'
+        AND name NOT LIKE 'pg_stat_monitor.pgsm_track_planning'
+ORDER
+BY      name
+COLLATE "C";
+
+\x
+
 DROP EXTENSION pg_stat_monitor;