Clean up isolation tests

Removed unused I2 step in cagg_multi_iso test. Removed waitpoint in cagg_concurrent_refresh test.

Author: kpan2034

tsl/test/isolation/expected/cagg_concurrent_refresh.out

@@ -258,34 +258,18 @@ step R12_refresh:
     CALL refresh_continuous_aggregate('cond2_10', 25, 70);
 
 
-starting permutation: WP_before_enable R1_refresh R3_refresh WP_before_release
+starting permutation: R1_refresh R3_refresh
 R5: LOG:  statement: 
     SET SESSION lock_timeout = '500ms';
     SET SESSION deadlock_timeout = '500ms';
     SET SESSION client_min_messages = 'DEBUG1';
 
-step WP_before_enable: 
-    SELECT debug_waitpoint_enable('before_process_cagg_invalidations_for_refresh_lock');
-
-debug_waitpoint_enable
-----------------------
-                      
-
 step R1_refresh: 
     CALL refresh_continuous_aggregate('cond_10', 25, 70);
- <waiting ...>
+
 step R3_refresh: 
     CALL refresh_continuous_aggregate('cond_10', 70, 107);
- <waiting ...>
-step WP_before_release: 
-    SELECT debug_waitpoint_release('before_process_cagg_invalidations_for_refresh_lock');
-
-debug_waitpoint_release
------------------------
-                       
 
-step R1_refresh: <... completed>
-step R3_refresh: <... completed>
 
 starting permutation: WP_after_materialization_enable R1_refresh WP_after_materialization_release R3_refresh
 R5: LOG:  statement: 

tsl/test/isolation/expected/cagg_multi_iso.out

@@ -1,4 +1,3 @@
-unused step name: I2
 Parsed test spec with 9 sessions
 
 starting permutation: Setup2 LockCAggCatalogRow_1 Refresh1 Refresh2 UnlockCAggCatalogRow_1

tsl/test/isolation/specs/cagg_concurrent_refresh.spec

@@ -488,8 +488,8 @@ permutation "R1_refresh" "R12_refresh"
 # TODO: pending materialization ranges not populated yet
 #permutation "WP_after_enable" "R6_pending_materialization_ranges" "R1_refresh"("WP_after_enable") "K1_cancelpid"("R1_refresh") "R6_pending_materialization_ranges" "WP_after_release" "R1_drop" "R6_pending_materialization_ranges_orphan"
 
-# R3 should wait for R1 to finish because there are cagg invalidation rows locked
-permutation "WP_before_enable" "R1_refresh"("WP_before_enable") "R3_refresh" "WP_before_release"
+# R3 should wait for R1 to finish because they serialize on the catalog tuple lock
+permutation "R1_refresh" "R3_refresh"
 
 # Concurrent refresh of caggs on non-overlapping ranges should not
 # block each other in the third transaction (materialization)

tsl/test/isolation/specs/cagg_multi_iso.spec

@@ -40,7 +40,6 @@ step "Setup2"
 
 session "I"
 step "I1"	{ INSERT INTO ts_continuous_test SELECT 0, i*10 FROM (SELECT generate_series(0, 10) AS i) AS i; }
-step "I2"   { INSERT INTO ts_continuous_test SELECT 40, 1000 ; }
 
 session "R1"
 setup { SET client_min_messages TO NOTICE; }