Sanitize device config returned from Oxidized (#8847)

DO NOT DELETE THIS TEXT

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When the output of a configuration file is parsed by Geshi it replaces quotes with html codes instead of leaving them as is. I have sanitized this back in to normal output.

html/pages/device/showconfig.inc.php

@@ -259,7 +259,7 @@ if (Auth::user()->hasGlobalAdmin()) {
         // $geshi->set_line_style('color: #999999');
         echo '<div class="config">';
         echo '<input id="linenumbers" class="btn btn-primary" type="submit" value="Hide line numbers"/>';
-        echo $geshi->parse_code();
+        echo htmlspecialchars_decode($geshi->parse_code());
         echo '</div>';
     }
 }//end if