finatra: fix finatra-thrift removal CHANGELOG entry location
finatra: fix finatra-thrift removal CHANGELOG entry location

Problem/Solution

The CHANGELOG location for D278231 was merged
into the 19.3 release changes, which is wrong.
This is an unreleased breaking change and has
been updated to reflect that.

Differential Revision: https://phabricator.twitter.biz/D296869

twitter/finatra,twitter/finatra,twitter/finatra