remove temporary lines

Author: vgvoleg

examples/topic/basic_example.py

@@ -7,7 +7,7 @@
 
 async def connect(endpoint: str, database: str) -> ydb.aio.Driver:
     config = ydb.DriverConfig(endpoint=endpoint, database=database)
-    # config.credentials = ydb.credentials_from_env_variables()
+    config.credentials = ydb.credentials_from_env_variables()
     driver = ydb.aio.Driver(config)
     await driver.wait(5, fail_fast=True)
     return driver

ydb/_grpc/grpcwrapper/ydb_topic.py

@@ -220,7 +220,6 @@ def to_proto(
                 proto.uncompressed_size = self.uncompressed_size
 
                 for key, value in self.metadata_items.items():
-                    # TODO: CHECK
                     item = ydb_topic_pb2.MetadataItem(key=key, value=value)
                     proto.metadata_items.append(item)