fix: add type: ignore for new InputValidationError calls

Author: blueeye-040

src/google/adk/artifacts/gcs_artifact_service.py

@@ -232,10 +232,12 @@ def _save_artifact(
       )
     elif artifact.file_data:
       if not artifact.file_data.file_uri:
-        raise InputValidationError("Artifact file_data must have a file_uri.")
+        raise InputValidationError(  # type: ignore[no-untyped-call]
+            "Artifact file_data must have a file_uri."
+        )
       if artifact_util.is_artifact_ref(artifact):
         if not artifact_util.parse_artifact_uri(artifact.file_data.file_uri):
-          raise InputValidationError(
+          raise InputValidationError(  # type: ignore[no-untyped-call]
               f"Invalid artifact reference URI: {artifact.file_data.file_uri}"
           )
       # Store the URI as blob metadata; no content to upload.