Destination BigQuery: use connector without credentials break in normalization step

[marcosmarxm]

Expected Behavior

Using Bigquery destination should work without credentials using normalization.

Current Behavior

#3947 makes credentials optional for bigquery but normalization need the credentials to run.

Logs

If applicable, please upload the logs from the failing operation. For sync jobs, you can download the full logs from the UI by going to the sync attempt page and clicking the download logs button at the top right of the logs display window.

Steps to Reproduce

Severity of the bug for you

Very low / Low / Medium / High / Critical

Airbyte Version

Found in the .env file in the root of the project.

Connector Version (if applicable)

Found in the admin page in the UI in the respective Source or Destination tab.

Additional context

Environment, version, integration...