Rust

Add `egui_kittest`, a test harness for egui #12867

Job	Run time
Format + check + test	32s
android	22s
cargo-deny aarch64-apple-darwin	40s
Check wasm32 + wasm-bindgen	2m 25s
cargo-deny aarch64-linux-android	38s
cargo-deny i686-pc-windows-gnu	38s
cargo-deny i686-pc-windows-msvc	37s
Check wasm32+atomics	1m 32s
cargo-deny i686-unknown-linux-gnu	39s
ios	21s
Check Windows	2m 9s
cargo-deny wasm32-unknown-unknown	38s
cargo-deny x86_64-apple-darwin	41s
cargo-deny x86_64-pc-windows-gnu	38s
cargo-deny x86_64-pc-windows-msvc	38s
cargo-deny x86_64-unknown-linux-gnu	39s
cargo-deny x86_64-unknown-linux-musl	35s
cargo-deny x86_64-unknown-redox	38s
	15m 0s

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