fix(ci): gatsby command

Author: benjie

scripts/deploy

@@ -5,7 +5,7 @@ DATE="$(date +%Y%m%d_%H%M%S)"
 git tag "deploy-${DATE}"
 git push --tags
 rm -rf .cache public __deploy
-gatsby build
+yarn gatsby build
 yarn test
 git clone "`git remote get-url origin`" __deploy
 cd __deploy