allow Local Parameters like countDistinct (#922)

Co-authored-by: Markus Kalkbrenner <[email protected]>

src/Component/Result/Stats/Result.php

@@ -157,7 +157,7 @@ public function getPercentiles(): ?array
      *
      * @return string|array|null
      */
-    protected function getValue($name)
+    public function getValue($name)
     {
         return $this->stats[$name] ?? null;
     }