util|finagle|finatra|twitter-server|scrooge: fix typo in CHANGELOG
util|finagle|finatra|twitter-server|scrooge: fix typo in CHANGELOG

Problem/Solution:

There is a typo in the Changelogs. The ScalaCheck version was updated, not
Scalatest. Fixed the typo.

Differential Revision: https://phabricator.twitter.biz/D701638

twitter/finatra,twitter/finatra,twitter/finatra