Update src/a2a/client/helpers.py

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: agilyol

src/a2a/client/helpers.py

@@ -9,8 +9,8 @@
 def create_text_message_object(
     role: Role = Role.user,
     content: str = '',
-    extensions: list[Any] | None = None,
-    metadata: dict[Any, Any] | None = None,
+    extensions: list[str] | None = None,
+    metadata: dict[str, Any] | None = None,
 ) -> Message:
     """Create a Message object containing a single TextPart.