empty cache after execute()

main.py

@@ -209,6 +209,7 @@ class PromptExecutor:
                 executed = set(executed)
                 for x in executed:
                     self.old_prompt[x] = copy.deepcopy(prompt[x])
+        torch.cuda.empty_cache()
 
 def validate_inputs(prompt, item):
     unique_id = item