catch Guzzle exceptions more liberally

Problem/Motivation

In makeSoapCall() we catch this:

    catch (RequestException $guzzle_exception) {

We need to be more liberal here.

For instance, if you haven't set the endpoint URL, you get a \GuzzleHttp\Exception\ConnectException which isn't caught.

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes