Misleading message when unable to connect due to DNS lookup failure.

[axisofentropy]

When the CLI cannot connect to a Uffizzi API server, users may receive a misleading error message:

$ docker run --interactive --rm --tty --entrypoint=bash uffizzi/cli
root@881228c80c70:~# uffizzi login
Login to Uffizzi to view and manage your previews.
Server:  https://devopseu.uffizzicloud.com
Username:  adam.vollrath@uffizzi.com
Password:  
The command was interrupted

This message should probably tell users that the CLI could not connect. In this case it's a DNS lookup failure. (devopseu.uffizzicloud.com is a CNAME that points to another record that no longer exists.)

[the38th]

looks like this was fixed in this commit

[AnnaPochepina]

tested

[NealArw]

TESTED on prod:

1. OK for case with invalid (unreached) URL

# uffizzi login
Login to Uffizzi to view and manage your previews.
Password:
A request was not sent to Uffizzi app

Other cases will be implement in #118