updated toc

Author: sreeram-venkitesh

keps/sig-node/4818-allow-zero-value-for-sleep-action-of-prestop-hook/README.md

@@ -95,7 +95,12 @@ tags, and then generate with `hack/update-toc.sh`.
       - [Integration tests](#integration-tests)
       - [e2e tests](#e2e-tests)
   - [Graduation Criteria](#graduation-criteria)
+    - [Alpha](#alpha)
+    - [Beta](#beta)
+    - [GA](#ga)
   - [Upgrade / Downgrade Strategy](#upgrade--downgrade-strategy)
+    - [Upgrade](#upgrade)
+    - [Downgrade](#downgrade)
   - [Version Skew Strategy](#version-skew-strategy)
 - [Production Readiness Review Questionnaire](#production-readiness-review-questionnaire)
   - [Feature Enablement and Rollback](#feature-enablement-and-rollback)