Gracefully handle UnknownHostException as a config

[ryankfu]

Tell us about the problem you're trying to solve

Add validation check for UnknownHostException within check stage. Currently, there's error handling that is caught within the discover phase and that later in the lifecycle for Airbyte. Preferably Airbyte catches this earlier. This follows after the conversation from here

Describe the solution you’d like

Add a validation check for pinging host within the check stage of Airbyte lifecycle

Describe the alternative you’ve considered or used

Additional context

N/A

Are you willing to submit a PR?

Remove this with your answer :-)

[bleonard]

Investigate if this is error in their setup. If so and we can reliably catch it, then:

1. return instructions for user
2. stack trace as a config_error
3. See if there is something to add to check - it has to be fast.

[akashkulk]

This is actually handled as a ConnectionErrorException
Which is handled at the top-level as a config-error. I think this can be closed - there is no action to take here. This would not create a Sentry crash. In addition, the workspace in question was Liren's test workspace