Included certificate won't work in new-ish K8S

To be able to use admission hooks, the server needs to be behind TLS.

There is a certificate/private key/CA included in this project. Unfortunately, they are signed with the SHA1 algorithm and new-ish K8s don't like that (SHA-256 is 

I would recommend including "-sha256" in openssl commands in ./dev/gen-certs.sh and regenerating them again.