Fix KEP Reference (kubernetes#7475)

Looks like the update script fails because it references a file whose name changed.  Fixing to match current state of community/master

https://github.com/kubernetes/community/blob/master/keps/0001-kubernetes-enhancement-proposal-process.md

Author: grodrigues3

update-imported-docs/community.yml

@@ -10,5 +10,5 @@ repos:
     dst: docs/imported/community/guide.md
   - src: mentoring/README.md
     dst: docs/imported/community/mentoring.md
-  - src: keps/1-kubernetes-enhancement-proposal-process.md
+  - src: keps/0001-kubernetes-enhancement-proposal-process.md
     dst: docs/imported/community/keps.md