Adding JWT fetch during health check for server connection

[avalerio-tkd]

• Added eager JWT fetching to DBPSApiClient::HealthCheck()
• Added unittest.

[avalerio-tkd]

@argmarco-tkd I tested the change in a couple ways and it looks fine (also added the unittest). Only if this only takes a few minutes, can you check if this behaves as expected on the testing you made before? If this takes longer than a few minutes to test, it should be fine to skip it. Thanks!

[argmarco-tkd]

@argmarco-tkd I tested the change in a couple ways and it looks fine (also added the unittest). Only if this only takes a few minutes, can you check if this behaves as expected on the testing you made before? If this takes longer than a few minutes to test, it should be fine to skip it. Thanks!

Ran tests from the av_add_auth_to_init_023 branch for the DBPS server.

When passing no credentials, and when using the wrong credentials, I got the following error Arrow side (I think this is expected):

/arrowdev/cpp/src/parquet/encryption/external/dbpa_executor.cc:101: [DBPAExecutor] EXCEPTION: init failed with: Health check failed: Health check succeeded but JWT fetch failed:  (status code: 401)
terminate called after throwing an instance of 'DBPSException'
  what():  Health check failed: Health check succeeded but JWT fetch failed:  (status code: 401)
Aborted

Things worked properly when passing the right credentials.

[argmarco-tkd]

LGTM - performed some testing, things behaved as-expected.

[avalerio-tkd]

Awesome. Thanks for checking this.