docs: update github issue template config

adds github discussions to the options

.github/ISSUE_TEMPLATE/config.yml

@@ -3,3 +3,6 @@ contact_links:
   - name: Support via Discord
     url: https://discord.gg/PkCWJSeCk7
     about: Chat with users and devs on support and setup related topics.
+  - name: Support via GitHub Discussions
+    url: https://github.com/sct/overseerr/discussions
+    about: Ask questions and discuss with other community members