Replace deprecated module and operator in example_tasks.py (#13527)

- `from airflow.utils.helpers import chain` to `from airflow.models.baseoperator import chain`

This commit also adds Bowler refactor for backport packages

airflow/providers/google/cloud/example_dags/example_tasks.py

@@ -29,6 +29,7 @@
 from google.protobuf import timestamp_pb2
 
 from airflow import models
+from airflow.models.baseoperator import chain
 from airflow.operators.bash import BashOperator
 from airflow.providers.google.cloud.operators.tasks import (
     CloudTasksQueueCreateOperator,
@@ -46,7 +47,6 @@
     CloudTasksTasksListOperator,
 )
 from airflow.utils.dates import days_ago
-from airflow.utils.helpers import chain
 
 timestamp = timestamp_pb2.Timestamp()
 timestamp.FromDatetime(datetime.now() + timedelta(hours=12))  # pylint: disable=no-member

dev/provider_packages/refactor_provider_packages.py

@@ -627,6 +627,13 @@ def pure_airflow_models_filter(node: LN, capture: Capture, filename: Filename) -
             """Check if select is exactly [airflow, . , models]"""
             return len(list(node.children[1].leaves())) == 3
 
+        def _contains_chain_in_import_filter(node: LN, capture: Capture, filename: Filename) -> bool:
+            if "module_import" in capture:
+                return bool("chain" in capture["module_import"].value) and filename.startswith(
+                    "./airflow/providers/google/"
+                )
+            return False
+
         os.makedirs(
             os.path.join(get_target_providers_package_folder("google"), "common", "utils"), exist_ok=True
         )
@@ -668,6 +675,12 @@ def pure_airflow_models_filter(node: LN, capture: Capture, filename: Filename) -
             .rename("airflow.providers.google.common.utils.process_utils")
         )
 
+        (
+            self.qry.select_module("airflow.models.baseoperator")
+            .filter(callback=_contains_chain_in_import_filter)
+            .rename("airflow.providers.google.common.utils.helpers")
+        )
+
         (
             self.qry.select_module("airflow.utils.helpers")
             .filter(callback=google_package_filter)