phive self-update not possible in CI because of unknown key

[sebastianfeldmann]

During CI I want to use the latest phive version.
So in one of my steps I'm calling phive self-update

Since the CI container does not know the phive gpg key it hangs with

Import this key? [y|N] 

It would be nice to have the --trusted-keys [key,key] options similar to the install command to not have to manually accept the key import.

Since it can only be the one key an option like --trust-key maybe is already enough.

[theseer]

I think we should just bundle the key with phive. But yes, valid point.