minor #623 Fixed PHPUnit doc URL (gnugat)

This PR was submitted for the 2.3-dev branch but it was merged into the 2.3 branch instead (closes #623).

Discussion
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Fixed PHPUnit doc URL

Any links to `www.phpunit.de` now redirects to the front page. Stripping `www.` off fixes the issue.

Commits
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e958959 Fixed PHPUnit doc URL

Author: fabpot

app/phpunit.xml.dist

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<!-- http://www.phpunit.de/manual/current/en/appendixes.configuration.html -->
+<!-- http://phpunit.de/manual/current/en/appendixes.configuration.html -->
 <phpunit
     backupGlobals               = "false"
     backupStaticAttributes      = "false"