Container-test: Add webdriver support

[810]

I have tried with

$this->taskSeleniumStandaloneServer()
	->setBinary("vendor/bin/selenium-server-standalone " . $this->getWebDriver() . ' >> selenium.log 2>&1 &')
	->runSelenium()
	->waitForSelenium()
	->run();

but it doesn't work, also without . ' >> selenium.log 2>&1 &'