Chore: Add breaking/core change link to issue templates (#13344)

Author: Kai Cataldo

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+ - name: Breaking/Core change
+ url: https://github.com/eslint/rfcs#how-to-submit-an-rfc
+ about: Please submit an RFC here.