Revert: Fixing error with link field with limited cardinality.

src/Plugin/GraphQL/DataProducer/FieldProducerPlugin.php

@@ -67,8 +67,8 @@ class FieldProducerPlugin extends DataProducerPluginBase implements FieldProduce
     }
 
     $results = [];
-    if (!empty($result = $this->resolveFieldItem($item, $context))) {
-      $results[] = $result;
+    foreach ($field as $item) {
+      $results[] = $this->resolveFieldItem($item, $context);
     }
 
     return $results;