feat(set_header): refactor and improve multiple header middleware#672

jlizen merged 5 commits into

tower-rs:maintower-rs/tower-http:mainfrom

seun-ja:571-add-multiple-headers-in-SetResponseHeaderLayer-or-similarseun-ja/tower-http:571-add-multiple-headers-in-SetResponseHeaderLayer-or-similarCopy head branch name to clipboard