Update apigee_edge_apiproduct_rbac.module

Changed from neutral to forbidden so that API Products do not show up on the assign operation or Create App when using the RBAC service to control access to API Products.  This is to solve issue apigee#1098

modules/apigee_edge_apiproduct_rbac/apigee_edge_apiproduct_rbac.module

@@ -67,7 +67,7 @@ function apigee_edge_apiproduct_rbac_api_product_access(EntityInterface $entity,
 
     if (empty($entity->getAttributeValue($rbac_attribute_name))) {
       if ('assign' === $operation) {
-        $result = AccessResult::neutral("{$operation} is not allowed on {$entity->label()} API product.");
+        $result = AccessResult::forbidden("{$operation} is not allowed on {$entity->label()} API product.");
       }
       elseif ($config->get('grant_access_if_attribute_missing')) {
         $result = AccessResult::allowed();
@@ -94,7 +94,7 @@ function apigee_edge_apiproduct_rbac_api_product_access(EntityInterface $entity,
       // Displaying these products should be solved on the form level always.
       if (empty(array_intersect($roles, $account->getRoles()))) {
         if ('assign' === $operation) {
-          $result = AccessResult::neutral("{$operation} is not allowed on {$entity->label()} API product.");
+          $result = AccessResult::forbidden("{$operation} is not allowed on {$entity->label()} API product.");
         }
         else {
           $result = _apigee_edge_user_has_an_app_with_product($entity->id(), $account, TRUE);