Merge pull request kubernetes#3948 from cici37/crdGA

KEP-2876: Clear Graduation Criteria for CRD validation rules to stable

Author: k8s-ci-robot

keps/sig-api-machinery/2876-crd-validation-expression-language/README.md

@@ -1134,8 +1134,10 @@ We plan to add e2e test under api-machinery for crd expression validation:
 
 #### GA
 
-- Formatted message. This targets in 1.27 and ideally should be in at least one release before going to GA.
-- Scalability evaluation. Evaluate CRD scalability with validation rules against [previous scale target](https://github.com/kubernetes/enhancements/blob/master/keps/sig-api-machinery/95-custom-resource-definitions/README.md#scale-targets-for-ga).
+- Formatted message. This has been added in 1.27.
+- Scalability evaluation. Evaluate CRD scalability with validation rules against [previous scale target](https://github.com/kubernetes/enhancements/blob/master/keps/sig-api-machinery/95-custom-resource-definitions/README.md#scale-targets-for-ga). The evaluation is available [here](https://docs.google.com/document/d/1gU8FfBhKnkmzJUC32NmXMdh4vzbLxb-gkf52O9Un7Cg/edit?usp=sharing)
+- Add optional fields reason and fieldPath into validation rules. 
+- Enable [CEL optional support](https://github.com/google/cel-spec/wiki/proposal-246) with proposed controlled rollout strategy. Ideally it should be in at least one release before going to GA.
 
 ## Production Readiness Review Questionnaire
 

keps/sig-api-machinery/2876-crd-validation-expression-language/kep.yaml

@@ -27,7 +27,7 @@ stage: beta
 # The most recent milestone for which work toward delivery of this KEP has been
 # done. This can be the current (upcoming) milestone, if it is being actively
 # worked on.
-latest-milestone: "v1.27"
+latest-milestone: "v1.28"
 
 # The milestone at which this feature was, or is targeted to be, at each stage.
 milestone: