replace path separators in model_name with underscores

evoprompt/models.py

@@ -133,7 +133,9 @@ class LLMModel(ABC):
             sort_keys=True,
         )
         cache_key = (
-            str(self.model_name) + '/' + hashlib.sha1(unique_options_key.encode()).hexdigest()
+            str(self.model_name).replace("/", "_")
+            + "/"
+            + hashlib.sha1(unique_options_key.encode()).hexdigest()
         )
         return cache_key