The GCStoGCS operator using the _replace=False_ flag and specifying _source_object != destination_object_, will not work properly, because it is comparing [apples](https://github.com/apache/airflow/blob/main/airflow/providers/google/cloud/transfers/gcs_to_gcs.py#L351) with [pears](https://github.com/apache/airflow/blob/0dd70de9492444d52e0afaadd7a510fc8a95369c/airflow/providers/google/cloud/transfers/gcs_to_gcs.py#L357).

Cause: the _prefix_ in the _pears_ case needs to be calculated from the _destination_object_, however, it is coming from the _source_object_.




tests/providers/google/cloud/transfers/test_gcs_to_gcs.py
mock_hook.return_value.list.return_value = SOURCE_OBJECTS_LIST
        operator = GCSToGCSOperator(
            task_id=TASK_ID, source_bucket=TEST_BUCKET, source_objects=SOURCE_OBJECTS_LIST
        )
        operator.execute(None)
        mock_calls = [
            mock.call(TEST_BUCKET, 'test_object/file1.txt', TEST_BUCKET, 'test_object/file1.txt'),
            mock.call(TEST_BUCKET, 'test_object/file2.txt', TEST_BUCKET, 'test_object/file2.txt'),
            mock.call(TEST_BUCKET, 'test_object/file3.json', TEST_BUCKET, 'test_object/file3.json'),
        ]
        mock_hook.return_value.rewrite.assert_has_calls(mock_calls)
    @mock.patch('airflow.providers.google.cloud.transfers.gcs_to_gcs.GCSHook')
    def test_wc_with_last_modified_time_with_all_true_cond_no_file(self, mock_hook):
        mock_hook.return_value.list.return_value = SOURCE_OBJECTS_LIST
        mock_hook.return_value.is_updated_after.side_effect = [True, True, True]
        operator = GCSToGCSOperator(
            task_id=TASK_ID,
            source_bucket=TEST_BUCKET,
            source_objects=SOURCE_OBJECTS_NO_FILE,
            destination_bucket=DESTINATION_BUCKET,
            last_modified_time=MOD_TIME_1,
        )
        operator.execute(None)
        mock_calls_none = [
            mock.call(TEST_BUCKET, 'test_object/file1.txt', DESTINATION_BUCKET, 'test_object/file1.txt'),
            mock.call(TEST_BUCKET, 'test_object/file2.txt', DESTINATION_BUCKET, 'test_object/file2.txt'),
            mock.call(TEST_BUCKET, 'test_object/file3.json', DESTINATION_BUCKET, 'test_object/file3.json'),
        ]
        mock_hook.return_value.rewrite.assert_has_calls(mock_calls_none)