add phpunit extension

phpunit.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit backupGlobals="false"
          backupStaticAttributes="false"
-         bootstrap="tests/bootstrap.php"
+         bootstrap="vendor/autoload.php"
          colors="true"
          convertErrorsToExceptions="true"
          convertNoticesToExceptions="true"
@@ -22,6 +22,9 @@
             <directory suffix=".php">./app</directory>
         </whitelist>
     </filter>
+    <extensions>
+        <extension class="Tests\Bootstrap"/>
+    </extensions>
     <php>
         <server name="APP_ENV" value="testing"/>
         <server name="BCRYPT_ROUNDS" value="4"/>