Show credentials with public IP as endpoint when dynds does not exist in CLI

[pablomendezroyo]

Wireguard credentials may have an empty endpoint if the dynds is not set by the dappmanager. The credentials shown in the CLI using the command dappnode_wireguard should show the credentials with the public IP if the dyndns does not exist.

• [ ] Get public IP and join it to the existing wireguard credentials if endpoint is empty: https://github.com/dappnode/DNP_WIREGUARD/blob/master/api/src/executables/getWireguardCredentials.ts
• [ ] Determine a beauty message to show in the CLI saying that this credentials should be something temporary since publc IPs may change

[pablomendezroyo]

exit 1 if URL is empty Closed by https://github.com/dappnode/DNP_WIREGUARD/pull/19#pullrequestreview-736895619 and https://github.com/dappnode/DNP_DAPPMANAGER/issues/882