KEP-127: Update documentation checkbox

We have documentation published for years. We have also shared the
design in mailing list and sig-node meetings. So, let's check those
boxes.

Signed-off-by: Rodrigo Campos <[email protected]>

Author: rata

keps/sig-node/127-user-namespaces/README.md

@@ -73,8 +73,8 @@ Items marked with (R) are required *prior to targeting to a milestone / release*
 - [X] (R) Production readiness review completed
 - [X] (R) Production readiness review approved
 - [X] "Implementation History" section is up-to-date for milestone
-- [ ] User-facing documentation has been created in [kubernetes/website], for publication to [kubernetes.io]
-- [ ] Supporting documentation—e.g., additional design documents, links to mailing list discussions/SIG meetings, relevant PRs/issues, release notes
+- [X] User-facing documentation has been created in [kubernetes/website], for publication to [kubernetes.io]
+- [X] Supporting documentation—e.g., additional design documents, links to mailing list discussions/SIG meetings, relevant PRs/issues, release notes
 
 [kubernetes.io]: https://kubernetes.io/
 [kubernetes/enhancements]: https://git.k8s.io/enhancements