Risky test

[fbourigault]

While playing with PHPUnit 6 and HttplugBundle, PHPUnit reported the following test as risky because nothing is asserted here.

HttplugBundle/Tests/Functional/DiscoveryTest.php

Lines 59 to 68 in 1627ff4

	public function testNoDiscoveryFallbacks()
	{
	$this->setDefinition('httplug.client.default', new Definition(HttpClient::class));
	$this->setDefinition('httplug.message_factory.default', new Definition(MessageFactory::class));
	$this->setDefinition('httplug.uri_factory.default', new Definition(UriFactory::class));
	$this->setDefinition('httplug.stream_factory.default', new Definition(StreamFactory::class));
	$this->setDefinition('httplug.async_client.default', new Definition(HttpAsyncClient::class));
	$this->load();
	}

What's the purpose of this test? I blindly added a new line in #174 and test the only history I have is when the test was added in #55 but as DiscoveryPassTest.