Auto merge of #4724 - lzutao:minor-appveyor, r=phansch
Auto merge of #4724 - lzutao:minor-appveyor, r=phansch

appveyor: minor syntax change

Use this link to review diff: https://github.com/rust-lang/rust-clippy/pull/4724/files?w=1
changelog: none

graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust