refactor: update license header in test_retention_strategies.py

Author: ForeverAngry

tests/table/test_retention_strategies.py

@@ -1,13 +1,19 @@
-#!/usr/bin/env python3
-"""
-Test script to validate the retention strategies implementation in MaintenanceTable.
-
-This script demonstrates the new retention features:
-1. retain_last_n_snapshots() - Keep only the last N snapshots
-2. expire_snapshots_older_than_with_retention() - Time-based expiration with retention constraints
-3. expire_snapshots_with_retention_policy() - Comprehensive retention policy
-"""
-
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
 from types import SimpleNamespace
 from unittest.mock import MagicMock
 from uuid import uuid4