chore(config) rm windows_wsl_setup_acknowledged (#22717)

## Summary
Remove dead code from a notice that no longer exists.

## Testing
- [x] Unit tests pass.

codex-rs/thread-manager-sample/src/main.rs

@@ -272,7 +272,6 @@ fn new_config(model: Option<String>, arg0_paths: Arg0DispatchPaths) -> anyhow::R
         suppress_unstable_features_warning: false,
         active_profile: None,
         active_project: ProjectConfig { trust_level: None },
-        windows_wsl_setup_acknowledged: false,
         notices: Notice::default(),
         check_for_update_on_startup: false,
         disable_paste_burst: false,