Update MasterSlaveConnectionTest.php

the test testKeepSlaveBeginTransactionStaysOnMaster does not begin a transaction, I have put a begin transaction, and now it fails,

the fix is here, if it makes sense
https://github.com/ananda-agrawal/dbal/commit/eb9262afb3955e4974d5a713b495a544b66a5cf7

tests/Doctrine/Tests/DBAL/Functional/MasterSlaveConnectionTest.php

@@ -94,8 +94,10 @@ class MasterSlaveConnectionTest extends DbalFunctionalTestCase
     {
         $conn = $this->createMasterSlaveConnection($keepSlave = true);
         $conn->connect('slave');
-
+    
+        $conn->beginTransaction();
         $conn->insert('master_slave_table', array('test_int' => 30));
+        $conn->commit();
 
         $this->assertTrue($conn->isConnectedToMaster());