migrate some bevy changes

[bayou-brogrammer]

1. Bevy time is now exported from bevy_time package bevyengine/bevy@644bd5d
2. Bevy removed Ortho camera and UI Camera. The 3d/2d cameras now handle UI elements [Merged by Bors] - Camera Driven Rendering bevyengine/bevy#4745
3. bevy::input::system::exit_on_esc_system is now bevy::window::close_on_esc
4. Rect is now UIRect for UI Elements
5. as_system_label is now not needed. (Screenshot taken from bevy source)

[inodentry]

Most of your changes are formatting changes. I'm guessing you either ran cargo fmt or your editor has auto-formatting. Could you please not do that? It makes it very hard to see what the commit actually changes.

I am personally not a fan of enforcing rustfmt autoformatting in my projects. I would rather everyone just commit things with some sensible (even if inconsistent) formatting in the first place, and avoid the noise/spam of the autoformatter.

[bayou-brogrammer]

Ah yeah I can fix it and try again. Pretty sure my vscode runs it automatically