chore: clippy on redundant closure (#4058)

Add redundant closure clippy rules and let Codex fix it by minimising
FQP

codex-rs/exec/src/event_processor_with_human_output.rs

@@ -573,7 +573,7 @@ impl EventProcessor for EventProcessorWithHumanOutput {
 }
 
 fn escape_command(command: &[String]) -> String {
-    try_join(command.iter().map(|s| s.as_str())).unwrap_or_else(|_| command.join(" "))
+    try_join(command.iter().map(String::as_str)).unwrap_or_else(|_| command.join(" "))
 }
 
 fn format_file_change(change: &FileChange) -> &'static str {