Use whole browser window

Taken from
https://johanhelsing.studio/posts/extreme-bevy

src/main.rs

@@ -8,7 +8,14 @@ use debug_plugin::BoidsDebugPlugin;
 
 fn main() {
     App::new()
-        .add_plugins(DefaultPlugins)
+        .add_plugins(DefaultPlugins.set(WindowPlugin {
+            primary_window: Some(Window {
+                fit_canvas_to_parent: true,
+                prevent_default_event_handling: false,
+                ..default()
+            }),
+            ..default()
+        }))
         .add_plugins(BoidsDebugPlugin)
         .add_plugins(BoidsPlugin)
         .run();