Add more defaults to the stdlib (#9606)

Continuing work towards #8988.

The first five commits were created using stubdefaulter on various Python versions; the following commits were all created manually by me to fix various problems. The main things this adds that weren't present in #9501 are:

- Defaults in Windows-only modules and Windows-only branches (because I'm running a Windows machine)
- Defaults in non-py311 branches
- Defaults for float parameters
- Defaults for overloads

stdlib/_weakrefset.pyi

@@ -13,7 +13,7 @@ _T = TypeVar("_T")
 
 class WeakSet(MutableSet[_T], Generic[_T]):
     @overload
-    def __init__(self, data: None = ...) -> None: ...
+    def __init__(self, data: None = None) -> None: ...
     @overload
     def __init__(self, data: Iterable[_T]) -> None: ...
     def add(self, item: _T) -> None: ...