ARROW-5768: [Release] Remove needless empty lines at the end of CHANGELOG.md
ARROW-5768: [Release] Remove needless empty lines at the end of CHANGELOG.md

Author: Sutou Kouhei <kou@clear-code.com>

Closes #4731 from kou/release-changelog-remove-newlines and squashes the following commits:

56765f8f9 <Sutou Kouhei>  Remove needless empty lines at the end of CHANGELOG.md

apache/arrow,apache/arrow,kou/arrow,wesm/arrow,renesugar/arrow,kou/arrow,cpcloud/arrow,icexelloss/arrow,apache/arrow,cpcloud/arrow,kou/arrow,icexelloss/arrow,laurentgo/arrow,majetideepak/arrow,laurentgo/arrow,xhochy/arrow,majetideepak/arrow,icexelloss/arrow,laurentgo/arrow,majetideepak/arrow,cpcloud/arrow,icexelloss/arrow,wesm/arrow,wesm/arrow,apache/arrow,majetideepak/arrow,xhochy/arrow,cpcloud/arrow,wesm/arrow,cpcloud/arrow,apache/arrow,renesugar/arrow,wesm/arrow,xhochy/arrow,cpcloud/arrow,renesugar/arrow,wesm/arrow,cpcloud/arrow,icexelloss/arrow,apache/arrow,renesugar/arrow,icexelloss/arrow,majetideepak/arrow,kou/arrow,xhochy/arrow,kou/arrow,wesm/arrow,laurentgo/arrow,xhochy/arrow,cpcloud/arrow,laurentgo/arrow,majetideepak/arrow,majetideepak/arrow,kou/arrow,kou/arrow,renesugar/arrow,renesugar/arrow,icexelloss/arrow,renesugar/arrow,icexelloss/arrow,kou/arrow,renesugar/arrow,cpcloud/arrow,laurentgo/arrow,apache/arrow,laurentgo/arrow,icexelloss/arrow,kou/arrow,majetideepak/arrow,apache/arrow,kou/arrow,renesugar/arrow,majetideepak/arrow,kou/arrow,apache/arrow,apache/arrow,laurentgo/arrow,kou/arrow,wesm/arrow,xhochy/arrow,xhochy/arrow,laurentgo/arrow,renesugar/arrow,wesm/arrow,icexelloss/arrow,renesugar/arrow,xhochy/arrow,xhochy/arrow,xhochy/arrow,xhochy/arrow,xhochy/arrow,laurentgo/arrow,cpcloud/arrow,wesm/arrow,laurentgo/arrow,wesm/arrow,xhochy/arrow,kou/arrow,majetideepak/arrow,majetideepak/arrow,cpcloud/arrow,cpcloud/arrow,apache/arrow,icexelloss/arrow,renesugar/arrow,apache/arrow,xhochy/arrow,majetideepak/arrow,renesugar/arrow,wesm/arrow,xhochy/arrow,renesugar/arrow,laurentgo/arrow,kou/arrow,renesugar/arrow,icexelloss/arrow,majetideepak/arrow,wesm/arrow,apache/arrow,majetideepak/arrow,cpcloud/arrow,majetideepak/arrow,icexelloss/arrow,laurentgo/arrow,laurentgo/arrow,laurentgo/arrow,cpcloud/arrow,icexelloss/arrow,wesm/arrow,apache/arrow