message: Use  for class.relationships
diff: import { getOwner } from '@ember/application';
  +import { get } from '@ember/object';
  import { computed } from '@ember/object';
  import { alias } from '@ember/object/computed';
  import Service, { inject as service } from '@ember/service';
  @@ -220,7 +221,7 @@ function ownedRelatedRecords(store, records, out = []) {
  }
  let recordClass = record.constructor;
  - recordClass.relationships.forEach(([ relationshipDefinition ]) => {
  + get(recordClass, 'relationships').forEach(([ relationshipDefinition ]) => {
  let { meta } = relationshipDefinition;
  let { owned } = meta.options;
  if (owned) {
  