Fix malformed arrays

Signed-off-by: Justin Kenyon <kenyonj@github.com>

Author: kenyonj

topics/actions/index.md

@@ -4,7 +4,7 @@ created_by: GitHub
 display_name: Actions
 github_url: https://github.com/actions
 logo: actions.png
-related: docker,ci
+related: docker, ci
 released: October 16, 2018
 short_description: GitHub Actions is a platform for developer workflow orchestration and automation.
 topic: actions