Stored info

[modular-magician]

Add support for DLP stored info type. This has a little more complex GET functionality as the API stores previous versions of the info type. I made name not user-settable, and only ever retrieve the current version of the stored info type.

Includes a little refactoring on previous DLP resources

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google_data_loss_prevention_stored_info_type

Derived from GoogleCloudPlatform/magic-modules#3922