Added updation capability in google_data_loss_prevention_stored_info_type resource

[modular-magician]

Added updation capability for dictionary, regex, and large_custom_dictionary fields in the google_data_loss_prevention_stored_info_type resource.

Added updation capability for the group_indexes subfield inside the regex field in the google_data_loss_prevention_stored_info_type resource.

fixes #8435

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• Ensured that all new fields I added that can be set by a user appear in at least one example (for generated resources) or third_party test (for handwritten resources or update tests).
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Release Note Template for Downstream PRs (will be copied)

dlp: Changed `dictionary`, `regex`, `regex.group_indexes` and `large_custom_dictionary` fields in `google_data_loss_prevention_stored_info_type` to be update-in-place

Derived from GoogleCloudPlatform/magic-modules#7601

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