GettextTranslationHelper: Avoid descending into symlinks

This basically avoids loops...

Signed-off-by: Eric Lippmann <eric.lippmann@icinga.com>

modules/translation/library/Translation/Util/GettextTranslationHelper.php

@@ -473,7 +473,7 @@ class GettextTranslationHelper
             $filepath = $directory . DIRECTORY_SEPARATOR . $filename;
             if (preg_match('@^[^\.].+\.(' . implode('|', $this->sourceExtensions) . ')$@', $filename)) {
                 $file->fwrite($filepath . PHP_EOL);
-            } elseif (is_dir($filepath)) {
+            } elseif (! is_link($filepath) && is_dir($filepath)) {
                 $subdirs[] = $filepath;
             }
         }