Make `databricks_entitlements` forward-compatible with new entitlements

[mgyucht]

trafficstars

Changes

The current implementation of databricks_entitlements crashes if an unexpected entitlement is returned from the API. This makes it impossible for new entitlements to be introduced and available by default. This is different from how most resources behave, where if new fields are added to resources in the API response, they are simply dropped rather than causing the provider to crash.

This PR is a clean-up of the handling of entitlements in the provider, both in the databricks_entitlements resource and the user, group and SP resources and data sources that expose entitlements. The entitlements are defined as a single entitlements structure which can be embedded in every SCIM structure. This makes it possible to use the standard StructToSchema, DataToStructPointer and StructToData methods that are ubiquitous throughout the SCIM API.

I removed the entitlements type alias and just use []ComplexValue in all places where that is used to minimize confusion with the new entitlements type. The methods on that type are no longer needed because the corresponding interactions are handled by the aforementioned methods.

As part of this cleanup, I have also ported the extra fields for the User, SP, Group and Entitlements resources to the struct definition, relying on StructToSchema to handle the transformation. This keeps the treatment of these APIs more uniform w.r.t. other resources on the plugin framework.

Tests

This should be a no-op change, so no new tests are needed.

The schema of the provider should not change as a result of this PR.