Logging when API calls fail lead users to believe the experiment failed

At the end of the Build Validation Script executions, some API calls are made to populate the summary. These calls can fail for a few reasons (e.g. lack of API authorization, networking issues). If they do fail, the user is presented with some cryptic errors in eye-catching red text:

```
Response status code: 0
ERROR: Unable to connect to server to fetch build scan https://develocity.example.com/s/foo
Response status code: 0
ERROR: Unable to connect to server to fetch build scan https://develocity.example.com/s/bar
```

Often, the user will then click the build scan links and see that they do in fact exist.

In these cases, when a user is running the script manually, the experiment will still provide users with the quick links for investigation, so the experiment was not entirely a failure. The lack of summary should be treated more like a warning. It would be good to be more helpful and let the user know what happened, what the impact was, and how to remediate it.