fix: fix 'isinstance-second-argument-not-valid-type' for pylint

.pylintrc

@@ -7,7 +7,6 @@ disable=fixme,
         attribute-defined-outside-init,
         consider-using-generator,
         duplicate-code,
-        isinstance-second-argument-not-valid-type,
         keyword-arg-before-vararg,
         missing-function-docstring,
         missing-module-docstring,

src/wuttaweb/forms/schema.py

@@ -381,7 +381,9 @@ class ObjectRef(colander.SchemaType):
         if not value:
             return None
 
-        if isinstance(value, self.model_class):
+        if isinstance(  # pylint: disable=isinstance-second-argument-not-valid-type
+            value, self.model_class
+        ):
             return value
 
         # fetch object from DB