MAGETWO-33616: MTF Configuration code clean up

dev/tests/functional/composer.json

 {
     "require": {
-        "magento/mtf": "1.0.0-rc20",
+        "magento/mtf": "1.0.0-rc21",
         "php": "~5.5.0|~5.6.0",
         "phpunit/phpunit": "4.1.0",
         "phpunit/phpunit-selenium": ">=1.2",

dev/tests/functional/phpunit.xml.dist

@@ -26,7 +26,6 @@
             </arguments>
         </listener>
         <listener class="Magento\Mtf\System\Event\StateListener" />
-        <listener class="Magento\Mtf\System\JUnit"/>
     </listeners>
 
     <php>
@@ -37,7 +36,6 @@
         <env name="log_directory" value="var/log" />
         <env name="events_preset" value="base" />
         <env name="module_whitelist" value="Magento_Install,Magento_Core" />
-        <env name="report_file_name" value="test-cases-report.xml"/>
         <env name="basedir" value="var/log" />
         <env name="credentials_file_path" value="./credentials.xml.dist" />
     </php>