MCM - Added link to SP toc for trbs-not-avail

Author: bandersmsft

articles/cost-management-billing/savings-plan/toc.yml

@@ -48,4 +48,6 @@
   - name: Troubleshoot
     items:
     - name: Troubleshoot utilization
-      href: troubleshoot-savings-plan-utilization.md
+      href: troubleshoot-savings-plan-utilization.md
+    - name: Not available due to conflict error
+      href: ../manage/troubleshoot-not-available-conflict.md