stdlib: fix many attributes which are read-only at runtime but read-write in the stub (#7395)

stdlib/weakref.pyi

@@ -128,5 +128,6 @@ class finalize:  # TODO: This is a good candidate for to be a `Generic[_P, _T]`
     def __call__(self, _: Any = ...) -> Any | None: ...
     def detach(self) -> tuple[Any, Any, tuple[Any, ...], dict[str, Any]] | None: ...
     def peek(self) -> tuple[Any, Any, tuple[Any, ...], dict[str, Any]] | None: ...
-    alive: bool
+    @property
+    def alive(self) -> bool: ...
     atexit: bool