fix: publish-website should not continue if it fails to checkout gh-pages

publish-website.sh

@@ -1,6 +1,7 @@
 #!/usr/bin/env bash
 
-git checkout gh-pages
+if git checkout gh-pages
+then
     rm -rf css
     rm -rf img
     rm -rf js
@@ -16,3 +17,4 @@ git add *
     git commit -m 'doc: Publish website'
     git push origin gh-pages
     git checkout master
+fi