github/pages-gem v216

on GitHub

• #772 – Remove gem-based themes, replace with remote themes
• #774 – Use Ruby 2.7.3

NOTE: When building Jekyll locally using one of the Jekyll themes included in GitHub Pages, you will need to upgrade your _config.yml:

-theme: jekyll-theme-hacker
+remote_theme: pages-themes/hacker@v0.1.1
+plugins:
+  - jekyll-remote-theme