out_bigquery: Add debug log for response payload when HTTP 200 OK

[oz-rw]

This commit adds debug logging of the response payload. Even with HTTP 200 OK status response, BigQuery may return an error message in the payload. This can lead to data not being inserted into BigQuery silently.

Now it is easier to detect such cases with debug logging:

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Testing
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• [N/A] Example configuration file for the change
• Debug log output from testing the change

[2024/04/19 07:59:05] [debug] [output:bigquery:bigquery.1] HTTP Status=200
[2024/04/19 07:59:05] [debug] [output:bigquery:bigquery.1] response
{
  "kind": "bigquery#tableDataInsertAllResponse",
  "insertErrors": [
    {
      "index": 0,
      "errors": [
        {
          "reason": "invalid",
          "location": "verticaluncertainty",
          "debugInfo": "",
          "message": "Invalid NUMERIC value: 5233.56298828125"
        }
      ]
    }
  ]
}

• [N/A] Attached Valgrind output that shows no leaks or memory corruption was found

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• [N/A] Run local packaging test showing all targets (including any new ones) build.
• [N/A] Set ok-package-test label to test for all targets (requires maintainer to do).

Documentation

• [N/A] Documentation required for this feature

Backporting

• [N/A] Backport to latest stable release.

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Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.