collab: Fix screen share aspect ratio on non-Mac platforms (#38517)

It was just a bunch of finnickery around UI layout. It affected Linux
too.



Release Notes:

* Fixed aspect ratio of peer screen share when using Linux/Windows
builds.

crates/livekit_client/src/remote_video_track_view.rs

@@ -97,8 +97,10 @@ impl Render for RemoteVideoTrackView {
                 self.previous_rendered_frame = Some(current_rendered_frame)
             }
             self.current_rendered_frame = Some(latest_frame.clone());
-            return gpui::img(latest_frame.clone())
+            use gpui::ParentElement;
+            return ui::h_flex()
                 .size_full()
+                .child(gpui::img(latest_frame.clone()).size_full())
                 .into_any_element();
         }