travis: Use latest shellcheck

.travis.yml

@@ -15,7 +15,6 @@ install:
   - wget "https://storage.googleapis.com/shellcheck/shellcheck-${scversion}.linux.x86_64.tar.xz"
   - tar --xz -xvf "shellcheck-${scversion}.linux.x86_64.tar.xz"
   - shellcheck() { "shellcheck-${scversion}/shellcheck" "$@"; }
-  - shellcheck --version
 
 script:
     - time ./neofetch --travis -v