clean up description about "pre-commit" hook
clean up description about "pre-commit" hook

This link is deleted by this:
https://github.com/kubernetes/community/commit/6b42e8126a7e36af4e880c922478f4ab1c066d00#diff-c61d1306839d4aa3fa96ff4bae197585L226

This is a dead link now.

bgrant0607/community,pwittrock/community,pwittrock/community,kubernetes/community,bgrant0607/community,kubernetes/community,kubernetes/community