Fix cache clearing of "attr" attribute on test monkey-patches

src/schematools/types.py

@@ -211,7 +211,15 @@ def __repr__(self) -> str:
         return f"{self.__class__.__name__}({self.data!r})"
 
     def __setitem__(self, key, value):
-        if key in self.data and key in self.__dict__:
+        """Check for changes to the dictionary data. Note this is also called on __init__()."""
+        if key == "auth" and key in self.data:
+            logger.warning("auth field is patched by tests")
+
+        if (
+            key in self.__dict__
+            and (prop := getattr(self.__class__, key, None)) is not None
+            and isinstance(prop, cached_property)
+        ):
             # Clear the @cached_property cache value
             del self.__dict__[key]
         super().__setitem__(key, value)