MONITORENUMPROC has [param0](https://github.com/marlersoft/zigwin32/blob/ec98bb4d9eea532320a8551720a9e3ec6de64994/win32/graphics/gdi.zig#L4730) as optional, but the [Win32 docs](https://learn.microsoft.com/en-us/windows/win32/api/winuser/nc-winuser-monitorenumproc) state that it is non-nullable.
MONITORENUMPROC has param0 as optional, but the Win32 docs state that it is non-nullable.