ARROW-4807: [Rust] Fix csv_writer benchmark
ARROW-4807: [Rust] Fix csv_writer benchmark

Author: Chao Sun <sunchao@apache.org>

Closes #3842 from sunchao/ARROW-4807 and squashes the following commits:

1e1f5400 <Chao Sun> ARROW-4807:  Fix csv_writer benchmark

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