Update phpunit.xml schema

Author: gapple

phpunit.xml.dist

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
 <phpunit
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.1/phpunit.xsd"
+        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+        xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.5/phpunit.xsd"
     failOnWarning="true"
 >
     <testsuites>