Docs : remove the description of the feature in preview

[sinbai]

Purpose of this PR:

• Remove the description of the cross-region replication feature in preview as the feature recently became generally available.
• Update test cases to test the generally available feature.

Test result:

PASS: TestAccMongoCluster_geoReplica
PASS: TestAccMongoCluster_previewFeature (2480.43s)
PASS: TestAccMongoClusterFreeTier/freeTier/update (3077.22s)

[stephybun]

In the acceptance test we're still setting preview_features = ["GeoReplicas"] in the config but in the notes it says this isn't required anymore?

[sinbai]

Although GeoReplicas is now generally available, the current API behavior is still supported for preview_features = ["GeoReplicas"]. Therefore, I still keep the test case for preview_features property. Do you mean I should remove that test case? Any feedback feel free to let me know, thank you.

[stephybun]

Our tests should validate that GeoReplicas work without having to set preview_features = ["GeoReplicas"] since that is what we have written in the docs.

You are right in that we should still have a test case for the preview_features property though, are there any other preview features that we can use here instead of GeoReplicas?

[sinbai]

Yes, you are right. I have updated TestAccMongoCluster_geoReplica test case and test passed. Currently, GeoReplicas still works for the preview_features property test, I'm already asking the service team if there are other values ​​other than GeoReplicas available. If so, I would update the tests.

[sinbai]

Hi @stephybun given the response provided by the service team below, I have deleted the validation of preview_features to avoid TF from continuously updating this list in the future. In addition, regarding the test case of preview_features, I assume that it is OK to always use GeoReplicas. What do you think?

We intend on 'previewFeatures' to have new values added in an ongoing manner that can be orthogonal to an API version release. We will publicly document new preview feature settings that customers can try, but we can't guarantee these will be tied to an API version release.

Preview features will eventually be made GA – this can mean the behavior becomes default on mongo clusters, or the feature state is no longer gated by the preview switch. Preview feature values for GA'd feature will continue to be supported for backwards compat, but will be effectively no-ops.

Clients/tools should not attempt to validate/assume what the allowed values – they should allow any string values in the array to be accepted.