Change embedding model return type to Callable

Co-authored-by: Simon <80467011+sorgfresser@users.noreply.github.com>

src/diart/models.py

@@ -28,7 +28,7 @@ def __init__(self, model_info, hf_token: Union[Text, bool, None] = True):
         self.model_info = model_info
         self.hf_token = hf_token
 
-    def __call__(self) -> Union[Model, PretrainedSpeakerEmbedding]:
+    def __call__(self) -> Callable:
         try:
             return Model.from_pretrained(self.model_info, use_auth_token=self.hf_token)
         except HTTPError: