Update the lastest milestone to v1.30

Author: Jeffwan

keps/sig-node/4176-cpumanager-spread-cpus-preferred-policy/kep.yaml

@@ -22,7 +22,7 @@ stage: alpha
 # 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: "v1.29"
+latest-milestone: "v1.30"
 
 # The milestone at which this feature was, or is targeted to be, at each stage.
 milestone: