add subject_id to transfer job project SA

[modular-magician]

Add subject_id attribute to the transfer job project SA data source, this will allow getting the subject id to create aws iam role assumable by google SA and reduce the need to static IAM keys on AWS side.

Closes #11149

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Release Note Template for Downstream PRs (will be copied)

transfer: added attribute `subject_id` to data source `google_storage_transfer_project_service_account`

Derived from GoogleCloudPlatform/magic-modules#5735

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