windows: Avoid recording minimized position to database (#9407)

Minimizing window records strange position to DB. When Zed is restarted,
the window goes far away.
<img width="975" alt="image"
src="https://github.com/zed-industries/zed/assets/6465609/98dbab71-fdbb-4911-b41a-9c3e498e5478">

So I fixed.

Release Notes:

- N/A

crates/gpui/src/platform.rs

@@ -170,6 +170,7 @@ unsafe impl Send for DisplayId {}
 pub(crate) trait PlatformWindow: HasWindowHandle + HasDisplayHandle {
     fn bounds(&self) -> Bounds<GlobalPixels>;
     fn is_maximized(&self) -> bool;
+    fn is_minimized(&self) -> bool;
     fn content_size(&self) -> Size<Pixels>;
     fn scale_factor(&self) -> f32;
     fn appearance(&self) -> WindowAppearance;