[Minor] Add support question template

.github/ISSUE_TEMPLATE/support_question.md

@@ -0,0 +1,15 @@
+---
+name: Support Question
+about: If you have a question 💬, please check out our Mailing lists or other support channels!
+
+---
+
+--------------^ Click "Preview" for a nicer view!
+We primarily use GitHub as an issue tracker; for usage and support questions, please check out these resources below. Thanks!
+
+---
+
+* Mailing list: https://lists.rspamd.com/mailman/listinfo (you can subscribe on that page or browse the archives)
+* Telegram channel: http://t.me/rspamd
+* Also have a look at the following page for more information on how to get support:
+  https://rspamd.com/support.html