Add support for custom info types to inspect template.

[modular-magician]

Fixes: hashicorp/terraform-provider-google#7625

Couple of fields not supported, as they are marked as deprecated or structure undocumented

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Release Note Template for Downstream PRs (will be copied)

dlp: added `custom_info_types` to `google_dlp_inspect_template`

Derived from GoogleCloudPlatform/magic-modules#4146