Get domain name from a URL

get-domain-name-from-url.js

/**
Developer comment
- we'll use regex to build few capturing groups with the next structure:
first: https://wwww
second: <the domain>
thrid: .<end of domain>
- than we pick the relevant group from the array (base on the code task requriement)
**/
function domainName(url){
  return url.match(/^(https?:\/\/)?([w]+\.)?([a-z0-9-]+)\.[a-z]+/)[3];
}