github: Add issue template config

https://help.github.com/en/github/building-a-strong-community/configuring-issue-templates-for-your-repository#configuring-the-template-chooser

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,8 @@
+blank_issues_enabled: false
+contact_links:
+  - name: GitHub Actions Community Forum
+    url: https://github.community/t5/GitHub-Actions/bd-p/actions
+    about: Please ask questions about GitHub Actions here.
+  - name: GitHub Pages help
+    url: https://help.github.com/en/github/working-with-github-pages
+    about: GitHub Pages documentaion here.