eframe: Add `NativeOptions::persistence_path` #11283

Job	Run time
android	21s
cargo-deny aarch64-apple-darwin	40s
cargo-deny aarch64-linux-android	40s
Check wasm32 + wasm-bindgen	2m 14s
Format + check + test	5m 17s
cargo-deny i686-pc-windows-gnu	40s
cargo-deny i686-pc-windows-msvc	39s
Check Windows	2m 26s
cargo-deny i686-unknown-linux-gnu	1m 22s
cargo-deny wasm32-unknown-unknown	38s
cargo-deny x86_64-apple-darwin	40s
cargo-deny x86_64-pc-windows-gnu	42s
cargo-deny x86_64-pc-windows-msvc	39s
cargo-deny x86_64-unknown-linux-gnu	42s
cargo-deny x86_64-unknown-linux-musl	43s
cargo-deny x86_64-unknown-redox	48s
	19m 11s

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