refactor(http-types): Remove http_types module and use external ic-http-types crate#73

mducroux merged 2 commits intomaindfinity/sol-rpc-canister:mainfrom

mducroux/XC-313-ic-http-types-cratedfinity/sol-rpc-canister:mducroux/XC-313-ic-http-types-crateCopy head branch name to clipboard