Use location local variable fix

Author: p1c2u

openapi_core/validators.py

@@ -120,7 +120,7 @@ def _get_raw_value(self, request, param):
         location = request.parameters[param.location.value]
 
         try:
-            raw = request.parameters[param.location.value][param.name]
+            raw = location[param.name]
         except KeyError:
             raise MissingParameter(
                 "Missing required `{0}` parameter".format(param.name))