dev/changelog: Remove obsolete `RSVP.denodeify()` call
dev/changelog: Remove obsolete `RSVP.denodeify()` call

`@octokit/rest` returns Promises directly these days...

thoov/ember-cli,jrjohnson/ember-cli,elwayman02/ember-cli,HeroicEric/ember-cli,mike-north/ember-cli,jgwhite/ember-cli,HeroicEric/ember-cli,kategengler/ember-cli,mike-north/ember-cli,elwayman02/ember-cli,balinterdi/ember-cli,balinterdi/ember-cli,ember-cli/ember-cli,jgwhite/ember-cli,mike-north/ember-cli,mike-north/ember-cli,kategengler/ember-cli,jgwhite/ember-cli,jgwhite/ember-cli,fpauser/ember-cli,ember-cli/ember-cli,asakusuma/ember-cli,raycohen/ember-cli,HeroicEric/ember-cli,thoov/ember-cli,buschtoens/ember-cli,buschtoens/ember-cli,asakusuma/ember-cli,thoov/ember-cli,fpauser/ember-cli,HeroicEric/ember-cli,fpauser/ember-cli,jrjohnson/ember-cli,ember-cli/ember-cli,fpauser/ember-cli,thoov/ember-cli,raycohen/ember-cli