[Backport v15.x] http: remove dead code from internal/http.js
To fix linter error in https://github.com/nodejs/node/pull/36889/checks?check_run_id=1688515238
/cc @danielleadams
PR-URL: #36630 Refs: #32329 Reviewed-By: Benjamin Gruenbaum benjamingr@gmail.com Reviewed-By: Luigi Pinca luigipinca@gmail.com Reviewed-By: Anna Henningsen anna@addaleax.net Reviewed-By: Rich Trott rtrott@gmail.com