Lint all unused variables (#5989)

* Enable F841

* Autofix

* Remove all unused variable assignment

server.py

@@ -563,7 +563,7 @@ class PromptServer():
                 for x in nodes.NODE_CLASS_MAPPINGS:
                     try:
                         out[x] = node_info(x)
-                    except Exception as e:
+                    except Exception:
                         logging.error(f"[ERROR] An error occurred while retrieving information for the '{x}' node.")
                         logging.error(traceback.format_exc())
                 return web.json_response(out)
@@ -599,8 +599,6 @@ class PromptServer():
         @routes.post("/prompt")
         async def post_prompt(request):
             logging.info("got prompt")
-            resp_code = 200
-            out_string = ""
             json_data =  await request.json()
             json_data = self.trigger_on_prompt(json_data)
 
@@ -832,7 +830,7 @@ class PromptServer():
         for handler in self.on_prompt_handlers:
             try:
                 json_data = handler(json_data)
-            except Exception as e:
+            except Exception:
                 logging.warning(f"[ERROR] An error occurred during the on_prompt_handler processing")
                 logging.warning(traceback.format_exc())