Update to Drupal 8.1.1. For more information, see https://www.drupal.org/node/2718713

core/modules/field/src/Tests/FieldHelpTest.php

@@ -37,7 +37,7 @@ class FieldHelpTest extends WebTestBase {
    * Test the Field module's help page.
    */
   public function testFieldHelp() {
-    // Login the admin user.
+    // Log in the admin user.
     $this->drupalLogin($this->adminUser);
 
     // Visit the Help page and make sure no warnings or notices are thrown.

core/modules/field/src/Tests/FieldUnitTestBase.php

@@ -1,10 +1,5 @@
 <?php
 
-/**
- * @file
- * Contains \Drupal\field\Tests\FieldUnitTestBase.
- */
-
 namespace Drupal\field\Tests;
 
 use Drupal\Component\Utility\Unicode;