[#28879][#28726] YSQL: Disable txn ddl and object locking in pg_partman-test

Summary:
While porting pg_partman in YSQL, we assumed that transactional ddl support doesn't exist. There are some non-trivial changes that need to be
made to support transactional ddl with pg_partman. So this revision disables txn ddl and object lock (since it depends on txn ddl) in pg_partman-test.

#28726 will be used to track the relevant work required to support txn ddl with pg_partman.
Jira: DB-18601, DB-18425

Test Plan:
Jenkins: test regex: .*PgPartmanTest.*

./yb_build.sh --cxx-test integration-tests_pg_partman-test

Reviewers: myang, bkolagani, rthallam

Reviewed By: bkolagani

Subscribers: yql

Differential Revision: https://phorge.dev.yugabyte.com/D47399

Author: dr0pdb

src/yb/integration-tests/pg_partman-test.cc

@@ -33,6 +33,12 @@ class PgPartmanTest : public MiniClusterTestWithClient<ExternalMiniCluster> {
     opts.enable_ysql = true;
     // (Auto Analyze #28389)
     opts.extra_tserver_flags.push_back("--ysql_enable_auto_analyze=false");
+    // TODO(#28726): Reenable once pg_partman supports transactional ddl.
+    opts.extra_tserver_flags.push_back("--ysql_yb_ddl_transaction_block_enabled=false");
+    opts.extra_tserver_flags.push_back("--enable_object_locking_for_table_locks=false");
+    opts.extra_tserver_flags.push_back(
+        Format("--allowed_preview_flags_csv=$0,$1",
+                "enable_object_locking_for_table_locks", "ysql_yb_ddl_transaction_block_enabled"));
 
     cluster_.reset(new ExternalMiniCluster(opts));
     ASSERT_OK(cluster_->Start());