Fixes ToolCallAccuracy raises ZeroDivisionError when called without any arguments. (#1685)

- Fixes: #1684 

1. Check for both empty dictionaries:
- If both refs and preds are empty, return 1.0 as you specified in your
logic.
2. Check for empty refs:
- If refs is empty but preds is not, return 0.0 since there's nothing to
compare.

Co-authored-by: ikka <[email protected]>

Author: sahusiddharth

src/ragas/metrics/_tool_call_accuracy.py

@@ -35,6 +35,11 @@ def init(self, run_config):
     async def _get_arg_score(
         self, preds: t.Dict[str, t.Any], refs: t.Dict[str, t.Any], callbacks: Callbacks
     ) -> float:
+        if not refs and not preds:
+            return 1.0
+        if not refs:
+            return 0.0
+
         score = 0.0
         for arg in refs.keys():
             if arg in preds: