fix: token calculation for streaming requests with tools (#34) (#39)

Author: vladisavvv

aidial_adapter_openai/utils/tokens.py

@@ -33,7 +33,8 @@ def calculate_tokens_per_message(
 
     prompt_tokens = tokens_per_message
     for key, value in message.items():
-        prompt_tokens += len(encoding.encode(value))
+        if type(value) == str:
+            prompt_tokens += len(encoding.encode(value))
         if key == "name":
             prompt_tokens += tokens_per_name