fix(theme mode subscription): avoid checking the keys because this interferes with the first value from the subscription

the check should be redundant, because we also later check whether the value has changed or not anyway

src/app/cosmic.rs

@@ -602,9 +602,6 @@ impl<T: Application> Cosmic<T> {
                 };
             }
             Action::SystemThemeModeChange(keys, mode) => {
-                if !keys.contains(&"is_dark") {
-                    return iced::Task::none();
-                }
                 if match THEME.lock().unwrap().theme_type {
                     ThemeType::System {
                         theme: _,