Update PaymentTest.php

Fix code style of PaymentTest.

Author: schurter-cw

app/code/Magento/Sales/Test/Unit/Model/Order/PaymentTest.php

@@ -20,6 +20,7 @@ class PaymentTest extends \PHPUnit_Framework_TestCase
     const TRANSACTION_ID = 'ewr34fM49V0';
 
     private $mockContext;
+    
     /**
      * @var Payment
      */
@@ -858,7 +859,6 @@ public function testUpdateOnlineTransactionApproved()
         $this->mockInvoice($this->transactionId);
         $this->mockResultTrueMethods($this->transactionId, $baseGrandTotal, $message);
 
-
         $this->orderMock->expects($this->once())
             ->method('getStoreId')
             ->willReturn($storeId);