Remove sample config file from cakephp tests.

Not having the config file ensures apps work without a config file.

src/Core/Plugin.php

@@ -119,8 +119,12 @@ class Plugin
             }
             return;
         }
+
         if (!Configure::check('pluginPaths')) {
-            Configure::load('plugins');
+            try {
+                Configure::load('plugins');
+            } catch (\Exception $e) {
+            }
         }
 
         $config += [

tests/test_app/config/plugins.php

@@ -1,4 +0,0 @@
-<?php
-$config = [
-    'plugins' => []
-];