Remove unused variable assignments

exceptions/page/MDpageParameterNotNumericException.php

@@ -12,8 +12,7 @@ final class MDpageParameterNotNumericException extends Exception {
      */
     public function errorMessage() {
         //error message
-        $errorMsg = 'Parameter: <b>' . $this->getMessage() . '</b> is not a valid, numeric values.';
-        return $errorMsg;
+        return 'Parameter: <b>' . $this->getMessage() . '</b> is not a valid, numeric values.';
 
     }
 }