hacks for running (and screenshotting) the examples in CI on a github runner

[mockersf]

Objective

• Enable capturing screenshots of all examples in CI on a GitHub runner

Solution

• Shorten duration of a run
• Disable desktop_app mode - as there isn't any input in CI, examples using this take way too long to run
• Change the default ClusterConfig - the runner are not able to do all the clusters with the default settings
• Send extra WindowResized events - this is needed only for the split_screen example, because CI doesn't trigger that event unlike all the other platforms

[nicopap]

I think it would be better if sed was replaced with git patch and patch files (inline would be fine).

Otherwise this would run the risk of breaking silently (git patch does fail noisily)

[mockersf]

moved to git patch, thanks for the idea! it makes it a lot clearer than my sed commands

[rparrett]

I'm assuming that this has been pretty well tested over at https://vleue.com/bevy-example-tests/ by this point?

Couple pieces of non-blocking feedback / future ideas while playing with this locally:

• It would be cool if there was a mode that exited immediately after screenshotting. Probably harder than it sounds with screenshotting happening in an async task in the render app?
• It would be cool if we could patch such that newly created windows do not steal focus. I can't seem to make this work on macos and opened rust-windowing/winit#3072

[mockersf]

I would like to merge this PR before the 0.12 to write a more complete story for the blog post. It already has the two approvals needed, but the last commit hasn't been reviewed yet. It adds a patch for window creation to ensure its position is always the same on windows, to be able to have a predictable cursor position in the window.

@rparrett or @nicopap (or someone else), could you give this a new approval? thanks!

[rparrett]

Still looking good to me. Have been using this PR in my own "local testing infrastructure."

[mockersf]

thanks!