minor #957 [app] updated PHPUnit configuration according to the current supported PHPUnit version. (hhamon)

This PR was merged into the 2.3 branch.

Discussion
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[app] updated PHPUnit configuration according to the current supported PHPUnit version.

Is it valid that we "support" PHPUnit 4.1 or shall we update to the latest supported version?

Commits
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76cdc21 [app] updated PHPUnit configuration according to the current supported PHPUnit version.

Author: Tobion

app/phpunit.xml.dist

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<!-- http://phpunit.de/manual/4.1/en/appendixes.configuration.html -->
+<!-- https://phpunit.de/manual/current/en/appendixes.configuration.html -->
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.1/phpunit.xsd"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.8/phpunit.xsd"
          backupGlobals="false"
          colors="true"
          bootstrap="bootstrap.php.cache"