Direct questions to GitHub Discussions (codesandbox#4002)

* Delete QUESTION.md

* Adding config.yml to direct folks adding questions to Discussions

I think this will work alongside existing templates for issues and features, but lets see...

Author: garethx

.github/ISSUE_TEMPLATE/QUESTION.md

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Question
+    url: https://github.com/codesandbox/codesandbox-client/discussions
+    about: Have any questions?