Issue #3492332: Add support for Storage entities (allie-micka)

Closes #3492332

src/Plugin/GraphQLCompose/EntityType/Group.php

@@ -9,6 +9,8 @@ use Drupal\graphql_compose\Plugin\GraphQLCompose\GraphQLComposeEntityTypeBase;
 /**
  * {@inheritdoc}
  *
+ * @see https://www.drupal.org/project/group
+ *
  * This is mostly a placeholder entity type.
  * Further works on the groups module is assumed in the future.
  * Probably via another contrib module.