I ended up upgrading Chef manually on the server as I couldn't using
knife-zero
`curl https://omnitruck.chef.io/install.sh | sudo bash -s -- -P chef -v 18.7.10`
This has been done with the help of `cookstyle` which is very useful to
learn about breaking changes and updates in Chef.
On wiki-1 I managed to update Chef up to 17.10.163. For version 18 I ran
into an issue with the omnibus installer returning a 404
Refs #500
