fix: missed on input -> input_payload on e5362f8e1808

I didn't realize the associate array was being turned into keyword
args. So I left x['input'] = input_payload 8-(.

roundup/rest.py

@@ -424,7 +424,7 @@ def execute(cls, instance, path, method, input_payload):
 
                 # zip the varlist into a dictionary, and pass it to the caller
                 args = dict(zip(list_vars, match_obj.groups()))
-                args['input'] = input_payload
+                args['input_payload'] = input_payload
                 return func(instance, **args)
         raise NotFound('Nothing matches the given URI')