Removes `CreatesApplication` (#6310)

tests/CreatesApplication.php

@@ -1,21 +0,0 @@
-<?php
-
-namespace Tests;
-
-use Illuminate\Contracts\Console\Kernel;
-use Illuminate\Foundation\Application;
-
-trait CreatesApplication
-{
-    /**
-     * Create a new application instance.
-     */
-    public function createApplication(): Application
-    {
-        $app = require __DIR__.'/../bootstrap/app.php';
-
-        $app->make(Kernel::class)->bootstrap();
-
-        return $app;
-    }
-}

tests/TestCase.php

@@ -6,5 +6,5 @@
 
 abstract class TestCase extends BaseTestCase
 {
-    use CreatesApplication;
+    //
 }