added bundle install on docs command

Author: patvice

.github/workflows/docs.yml

@@ -44,6 +44,7 @@ jobs:
         # Outputs to the './_site' directory by default
         run: |
           cd ./docs
+          bundle install
           bundle exec jekyll build --baseurl "${{ steps.pages.outputs.base_path }}"
         env:
           JEKYLL_ENV: production