fix combine token

app/ner/services/ner.py

@@ -56,7 +56,7 @@ class NER:
         
         return extracted_entities
 
-    def _combine_token(tokens: list[str]) -> str:
+    def _combine_token(self, tokens: list[str]) -> str:
         """Combines tokens into a single string, removing leading hashtags from the first token if present.
         Args:
             tokens (list[str]): List of tokens to combine.