Add documentation for Storage Intelligence data sources.

[kautikdk]

Adds documentation of GCS Storage Intelligence data sources,

Implementation PRs,
Project SI resource: #12689
Folder SI resource: #13394
Organization SI resource: #13386

`google_storage_control_project_intelligence_config`

`google_storage_control_folder_intelligence_config`

`google_storage_control_organization_intelligence_config`

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 96 insertions(+))
google-beta provider: Diff ( 3 files changed, 96 insertions(+))

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