Stabilize `#[unix_sigpipe = "sig_dfl"]` on `fn main()`#120832

Enselic wants to merge 2 commits intorust-lang:masterrust-lang/rust:masterfrom

Enselic:stabilize-unix_sigpipe-sig_dflEnselic/rust:stabilize-unix_sigpipe-sig_dflCopy head branch name to clipboard