Add a debug outlines scene to the testbed_ui example #22019
Description
What problem does this solve or what need does it fill?
The debug_overlay module is easy to forget and has been broken mutliple times recently by UI changes. There should be some simple CI check in place to ensure it's working.
More discussion at #21091
What solution would you like?
- Add a debug outlines scene to
testbed_ui. This scene should be behind a#[cfg(feature = "bevy_ui_debug")]gate. - Enable the
"bevy_ui_debug"feature for thetestbed_uiscreenshot CI checks.