keps/sig-testing: declare 714 stable

specifically:

- drop quote-wrapping
- add prod-readiness file for this, but since this related to code that
  doesn't actually end up in a kubernetes release artifact that is used
  to create a kubernetes cluster, it's not clear that PRR is required

keps/sig-testing/714-break-test-tarball/README.md

@@ -276,3 +276,5 @@ Similar discussion and work on the other release tarballs:
   created, deprecation notice included in mondo test tarball
 - 2019-02-22: implementation https://github.com/kubernetes/kubernetes/pull/74065
   merged
+- 2019-09-24: Stop building kubernetes-test.tar.gz: https://github.com/kubernetes/kubernetes/pull/83093
+- 2021-08-16: Retroactive stable declaration

keps/sig-testing/714-break-test-tarball/kep.yaml

@@ -1,17 +1,24 @@
 title: Breaking apart the Kubernetes test tarball
 kep-number: 714
+scope: in-tree
 authors:
-  - "@ixdy"
+- ixdy
 owning-sig: sig-testing
 participating-sigs:
-  - sig-release
+- sig-release
 reviewers:
-  - "@akutz"
-  - "@amwat"
+- akutz
+- amwat
 approvers:
-  - "@spiffxp"
-  - "@tpepper"
-editor: TBD
+- spiffxp
+- tpepper
+editor: spiffxp
 creation-date: 2019-01-18
-last-updated: 2019-03-06
+last-updated: 2021-08-16
 status: implemented
+stage: stable
+latest-milestone: v1.17
+milestones:
+  alpha: v1.14
+  beta: v1.14
+  stable: v1.17