Refined OAuth Scopes for Transfer Config Management

The create and patch methods for projects.locations.transferConfigs and projects.transferConfigs have updated their recommended OAuth scopes. The primary scope has shifted from https://www.googleapis.com/auth/cloud-platform to https://www.googleapis.com/auth/bigquery. The cloud-platform scope is still listed as an alternative, ensuring backward compatibility. Developers are encouraged to adopt the more specific bigquery scope for improved security and least privilege.