Fix deprecation warning for return_all_scores (#19217)

* Improve deprecation warning for return_all_scores

* Fix formatting

src/transformers/pipelines/text_classification.py

@@ -87,7 +87,9 @@ class TextClassificationPipeline(Pipeline):
             postprocess_params["_legacy"] = False
         elif return_all_scores is not None:
             warnings.warn(
-                "`return_all_scores` is now deprecated, use `top_k=1` if you want similar functionnality", UserWarning
+                "`return_all_scores` is now deprecated,  if want a similar funcionality use `top_k=None` instead of"
+                " `return_all_scores=True` or `top_k=1` instead of `return_all_scores=False`.",
+                UserWarning,
             )
             if return_all_scores:
                 postprocess_params["top_k"] = None