Fix phpunit

Author: slavcodev

phpunit.xml.dist

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-		 xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/6.3/phpunit.xsd"
+		 xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/7.5/phpunit.xsd"
 		 bootstrap="vendor/autoload.php"
 		 failOnRisky="true"
 		 failOnWarning="true"