added new test metrics interceptor file

Author: daniel-sanche

tests/unit/data/_async/test_metrics_interceptor.py

@@ -0,0 +1,21 @@
+# Copyright 2025 Google LLC
+#
+# Licensed 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 google.cloud.bigtable.data._cross_sync import CrossSync
+
+
+__CROSS_SYNC_OUTPUT__ = "tests.unit.data._sync_autogen.test_metrics_interceptor"
+
+@CrossSync.convert_class
+class TestMetricsInterceptor: