http: use more destructuring

PR-URL: https://github.com/nodejs/node/pull/19481


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Jackson Tian <shyvo1987@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>