Update link to contributors page
Update link to contributors page

* GitHub changed their linking structure

naveed-ahmad/clearance,benlivermore/clearance,janusnic/clearance,zernie/clearance,zernie/clearance,thoughtbot/clearance,pedrosmmoreira/clearance,janusnic/clearance,naveed-ahmad/clearance,naveed-ahmad/clearance,benlivermore/clearance,benlivermore/clearance,thoughtbot/clearance,pedrosmmoreira/clearance,sferik/clearance,janusnic/clearance,thoughtbot/clearance,zernie/clearance,pedrosmmoreira/clearance