Fix ResourceFormTest

Add function-mock for mysqlAvaialable to prevent the unit test from breaking

test/php/application/forms/Config/Resource/ResourceFormTest.php

@@ -261,6 +261,8 @@ class ResourceFormTest extends BaseTestCase
     protected function setUpResourceFactoryMock($resourceMock)
     {
         Mockery::mock('alias:Icinga\Data\ResourceFactory')
+            ->shouldReceive('mysqlAvailable')
+            ->andReturn(true)
             ->shouldReceive('createResource')
             ->with(Mockery::type('\Zend_Config'))
             ->andReturn($resourceMock);