chore: redirect feature requests to rfc discussion

Author: yyx990803

.github/ISSUE_TEMPLATE/config.yml

@@ -1,5 +1,8 @@
 blank_issues_enabled: false
 contact_links:
+  - name: Feature Request
+    url: https://github.com/vuejs/rfcs/discussions
+    about: Suggest new features for consideration
   - name: Discord Chat
     url: https://chat.vuejs.org
     about: Ask questions and discuss with other Vue users in real time.