[fix] #366 fix etcd pod failed to exit init container

[koba1t]

fix : https://github.com/coreos/vault-operator/issues/366

I tried Getting start on README.md and apply configs on example/ dir. but, vault didn't start. Because etcd-operator fail to exit init container and don't start.

This problem is bug of etcd-operator version 0.8.3. It fixed to version 0.8.4. https://github.com/coreos/etcd-operator/blob/master/CHANGELOG.md

Please update etcd-operator from example/ dir.

[RyukerLiu]

Thank you. I've stuck by the example for a long time.