Fix: typo Bearer token (#8998)

### What problem does this PR solve?

Typo Bearer token. #8960

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

rag/llm/embedding_model.py

     _special_tokens = ["<|endoftext|>"]
 
     def __init__(self, key, model_name, **kwargs):
-        self.client = Client(host=kwargs["base_url"]) if not key or key == "x" else Client(host=kwargs["base_url"], headers={"Authorization": f"Bear {key}"})
+        self.client = Client(host=kwargs["base_url"]) if not key or key == "x" else Client(host=kwargs["base_url"], headers={"Authorization": f"Bearer {key}"})
         self.model_name = model_name
 
     def encode(self, texts: list):

rag/llm/tts_model.py

         self.base_url = base_url
         self.headers = {"Content-Type": "application/json"}
         if key and key != "x":
-            self.headers["Authorization"] = f"Bear {key}"
+            self.headers["Authorization"] = f"Bearer {key}"
 
     def tts(self, text, voice="standard-voice"):
         payload = {"model": self.model_name, "voice": voice, "input": text}