Allow disabling inclusion of bigquery-public-data in Power BI Google BigQuery connector

[vivek12344]

Customers using Power BI semantic models connected to Google Big Query via service account authentication have reported that, despite configuring models to use only internal datasets, the connector automatically includes big query-public-data in the connection string. This results in external datasets appearing in the navigator experience, which is unexpected and raises compliance concerns.

Currently, there is no parameter or configuration option to override this behavior. We propose adding a feature to allow disabling the inclusion of big query-public-data when connecting to Big Query.