Add proper title

Author: amwat

keps/sig-testing/2464-kubetest2-ci-migration/README.md

@@ -58,7 +58,7 @@ If none of those approvers are still appropriate, then changes to that list
 should be approved by the remaining approvers and/or the owning SIG (or
 SIG Architecture for cross-cutting KEPs).
 -->
-# KEP-NNNN: Your short, descriptive title
+# KEP-2464: Kubetest2 CI migration
 
 <!--
 This is the title of your KEP. Keep it short, simple, and descriptive. A good