remove unneeded validation after streaming

the validators are called with partial=False as part of validate_response_output in _marked_completed

Author: petersli

pydantic_ai_slim/pydantic_ai/result.py

@@ -114,20 +114,11 @@ async def stream_text(self, *, delta: bool = False, debounce_by: float | None =
             async for text in self._stream_response_text(delta=True, debounce_by=debounce_by):
                 yield text
         else:
-            last_text: str | None = None
             async for text in self._stream_response_text(delta=False, debounce_by=debounce_by):
                 for validator in self._output_validators:
                     text = await validator.validate(text, self._run_ctx, partial=True)  # pragma: no cover
-                last_text = text
                 yield text
 
-            if last_text is not None:
-                validated_text = last_text
-                for validator in self._output_validators:
-                    validated_text = await validator.validate(validated_text, self._run_ctx)
-                if validated_text != last_text:
-                    yield validated_text
-
     # TODO (v2): Drop in favor of `response` property
     def get(self) -> _messages.ModelResponse:
         """Get the current state of the response."""