fix(x-editable): choice value update crash with 0 value

Because of the weak comparison, if we try to update a choice list field
with a value of 0, it is considered as a violation.

src/Action/SetObjectFieldValueAction.php

@@ -225,7 +225,7 @@ public function __invoke(Request $request): JsonResponse
                 $value = $dataTransformer->reverseTransform($value);
             }
 
-            if (!$value && FieldDescriptionInterface::TYPE_CHOICE === $fieldDescription->getType()) {
+            if (null === $value && FieldDescriptionInterface::TYPE_CHOICE === $fieldDescription->getType()) {
                 return new JsonResponse(sprintf(
                     'Edit failed, object with id: %s not found in association: %s.',
                     $originalValue,