Merge pull request #4 from sunrise-php/renovate/phpunit-phpunit-7.x

Update dependency phpunit/phpunit to v7.5.4

Author: fenric

composer.json

@@ -17,7 +17,7 @@
         "sunrise/uri": "^1.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "7.5.1",
+        "phpunit/phpunit": "7.5.4",
         "fig/http-message-util": "1.1.3",
         "php-http/psr7-integration-tests": "dev-master"
     },