settings ui: Change window kind from floating to normal (#45401)

#40291 made floating windows always stay on top, which made the settings
ui window always on top of Zed. To maintain the old behavior, this PR
changes the setting window to be a normal window.

Release Notes:

- N/A

crates/settings_ui/src/settings_ui.rs

@@ -602,7 +602,7 @@ pub fn open_settings_editor(
                 focus: true,
                 show: true,
                 is_movable: true,
-                kind: gpui::WindowKind::Floating,
+                kind: gpui::WindowKind::Normal,
                 window_background: cx.theme().window_background_appearance(),
                 app_id: Some(app_id.to_owned()),
                 window_decorations: Some(window_decorations),