[Cyclenerd]

Adds the missing values to the subscription_tier field of google_discovery_engine_license_config so it accepts every tier the Discovery Engine API supports. Right now, setting a tier such as SUBSCRIPTION_TIER_ENTERPRISE_EMERGING fails at plan time with an expected subscription_tier to be one of [...] error, even though the API accepts it.

The following values from the SubscriptionTier API reference were added to mmv1/products/discoveryengine/LicenseConfig.yaml, in the same order as the API docs:

• SUBSCRIPTION_TIER_ENTERPRISE_EMERGING
• SUBSCRIPTION_TIER_EDU_EMERGING
• SUBSCRIPTION_TIER_EDU_PRO_EMERGING
• SUBSCRIPTION_TIER_FRONTLINE_STARTER
• SUBSCRIPTION_TIER_CONSUMPTION_ONLY
• SUBSCRIPTION_TIER_EDU_GOV_EMERGING

The enum now matches the API's full list of 16 values.

Breaking changes: None. The change only adds allowed values to the client-side enum validation, so every existing configuration stays valid.

Versions: The field already exists in both the google and google-beta providers, so the change applies to both.

Tests: No acceptance test was added. The resource's only generated example sets exclude_test: true because creating license configs at the project level is deprecated for Gemini Enterprise, so this resource can't currently be created in the test environment. The change only adds enum values; there is no new schema, expand/flatten or custom code. Generated code was checked locally: ValidateEnum and the field documentation in resource_discovery_engine_license_config.go list all the new values.

Documentation: Field documentation is generated from the YAML, and the "Possible values" list updates automatically.

Fixes hashicorp/terraform-provider-google#30632

discoveryengine: added `SUBSCRIPTION_TIER_ENTERPRISE_EMERGING`, `SUBSCRIPTION_TIER_EDU_EMERGING`, `SUBSCRIPTION_TIER_EDU_PRO_EMERGING`, `SUBSCRIPTION_TIER_FRONTLINE_STARTER`, `SUBSCRIPTION_TIER_CONSUMPTION_ONLY`, and `SUBSCRIPTION_TIER_EDU_GOV_EMERGING` as supported values for `subscription_tier` in `google_discovery_engine_license_config` resource

[github-actions]

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