Add available_features alias on namespace type

What does this MR do and why?

This MR adds the available_features field to the namespace type, and alias's this to licensed_features field, as a step towards renaming licensed_features -> available_features.

References

• #554931 (closed)

Screenshots or screen recordings

Not provided

How to set up and validate locally

1. In an environment with the GDK running, navigate to http://localhost:3000/-/graphql-explorer
2. Write a query to fetch available features and licensed features from the namespace. e.g:

query q {
  namespace(fullPath: "flightjs") {
    availableFeatures {
      hasEpicsFeature
      hasIssuableHealthStatusFeature
      hasIssueDateFilterFeature
      hasIssueWeightsFeature
      hasIterationsFeature
      hasLinkedItemsEpicsFeature
      hasOkrsFeature
      hasQualityManagementFeature
      hasScopedLabelsFeature
      hasSubepicsFeature
    }
    licensedFeatures {
      hasEpicsFeature
      hasIssuableHealthStatusFeature
      hasIssueDateFilterFeature
      hasIssueWeightsFeature
      hasIterationsFeature
      hasLinkedItemsEpicsFeature
      hasOkrsFeature
      hasQualityManagementFeature
      hasScopedLabelsFeature
      hasSubepicsFeature
    }
  }
}

3. Observe that the values match

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.