[#22184] YSQL: Fix DDL Atomicity drop table

Summary:
The the fix for #22095 (c8c2616/D34431) has caused the drop table DDL to return to the user as soon as the table is marked as DELETING. Prior to the change we used to wait till the table reached the state DELETED. This causes a bunch of test failures when atomic DDL is enabled.

The fix removed the DdlTransactionState early causing the early exit from drop table DDL.

The primary issue is from `CatalogManager::ShouldDeleteTable`. This function returns false when the table has any tasks. DDL atomicity runs the `TableSchemaVerificationTask` which causes this function to return false, causing the table to be lazily deleted in the async background task. The check is only meant to wait for DeleteReplica RPCs to complete, so a better fix is to change this check to be more specific and keep the original cleanup logic.
Jira: DB-11111

Test Plan:
Jenkins
Verified by merging with #D30471

Reviewers: myang

Reviewed By: myang

Subscribers: ybase

Differential Revision: https://phorge.dev.yugabyte.com/D34601

src/yb/master/catalog_manager.cc

@@ -6718,8 +6718,9 @@ bool CatalogManager::ShouldDeleteTable(const TableInfoPtr& table) {
                           << "Table Information is null. Skipping updating its state to DELETED.";
     return false;
   }
-  if (table->HasTasks()) {
-    VLOG_WITH_PREFIX_AND_FUNC(2) << table->ToString() << " has tasks";
+  // Wait for all the replica delete tasks that were sent to all peers to complete.
+  if (table->HasTasks(server::MonitoredTaskType::kDeleteReplica)) {
+    VLOG_WITH_PREFIX_AND_FUNC(2) << table->ToString() << " has more replica delete tasks";
     return false;
   }
   bool hide_only;

src/yb/master/ysql_ddl_handler.cc

@@ -406,11 +406,7 @@ Status CatalogManager::YsqlDdlTxnDropTableHelper(const YsqlTableDdlTxnState txn_
   dtreq.mutable_table()->set_table_name(table->name());
   dtreq.mutable_table()->set_table_id(table->id());
   dtreq.set_is_index_table(table->is_index());
-  RETURN_NOT_OK(DeleteTableInternal(&dtreq, &dtresp, nullptr /* rpc */, txn_data.epoch));
-
-  RemoveDdlTransactionState(table->id(), {txn_data.ddl_txn_id});
-
-  return Status::OK();
+  return DeleteTableInternal(&dtreq, &dtresp, nullptr /* rpc */, txn_data.epoch);
 }
 
 Status CatalogManager::WaitForDdlVerificationToFinish(