[decorator] Fix FunctionMaker attributes

- Closes: #14286
- Source: https://github.com/micheles/decorator/blob/e5cfd35413ea35ae41fde089db86a272ba8b5582/src/decorator.py#L82
- `FullArgSpec` types: https://github.com/python/typeshed/blob/cbd732e9c565ebae26afdecd4663fcc61273df80/stdlib/inspect.pyi#L492

Author: donbarbos

stubs/decorator/decorator.pyi

@@ -20,9 +20,9 @@ class FunctionMaker:
     args: list[str]
     varargs: str | None
     varkw: str | None
-    defaults: tuple[Any, ...]
+    defaults: tuple[Any, ...] | None
     kwonlyargs: list[str]
-    kwonlydefaults: str | None
+    kwonlydefaults: _dict[str, Any] | None
     shortsignature: str | None
     name: str
     doc: str | None