Merge branch 'master' of https://github.com/github/opensource.guide into develop

Author: asf0828

Gemfile.lock

@@ -84,7 +84,7 @@ GEM
     html-pipeline (2.11.0)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    html-proofer (3.11.0)
+    html-proofer (3.11.1)
       activesupport (>= 4.2, < 6.0)
       addressable (~> 2.3)
       mercenary (~> 0.3.2)