chore(github): add issue templates configuration file

- disable blank issues
- add contact links

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,11 @@
+blank_issues_enabled: false
+contact_links:
+  - name: You need configuration help
+    url: https://github.com/qdm12/gluetun/discussions/new
+    about: Please create a Github discussion.
+  - name: Report a Gluetun bug or feature request
+    url: https://github.com/qdm12/gluetun/issues/new
+    about: Please create an issue on the gluetun repository.
+  - name: Unraid template issue
+    url: https://github.com/qdm12/gluetun/discussions/550
+    about: Please read the relevant Github discussion.