message: cleanup unused fields
  These seem to be leftovers from refactorings.
diff: @@ -264,13 +264,6 @@ const models = [
  'field-type': '@cardstack/core-types::string'
  }
  },
  - {
  - type: 'fields',
  - id: 'searchable-relationships',
  - attributes: {
  - 'field-type': '@cardstack/core-types::string-array'
  - }
  - },
  {
  type: 'fields',
  id: 'default-includes',
  @@ -396,13 +389,6 @@ const models = [
  'field-type': '@cardstack/core-types::object'
  }
  },
  - {
  - type: 'fields',
  - id: 'group-id',
  - attributes: {
  - 'field-type': '@cardstack/core-types::string'
  - }
  - },
  {
  type: 'fields',
  id: 'value',
  