Use Standards::isInstalledStandard() instead of Standards::getInstalledStandards()

Author: rodrigoprimo

Scripts/DocCodeExamples/XmlDocValidator.php

@@ -128,9 +128,7 @@ public function __construct(
         $subset         = $dirs[\count($dirs) - 1];
         $this->sniff    = $this->standard . '.' . $subset . '.' . \str_replace('Standard', '', $pathInfo['filename']);
 
-        $standards = Standards::getInstalledStandards(true);
-
-        if (\in_array($this->standard, $standards, true) === false) {
+        if (Standards::isInstalledStandard($this->standard) === false) {
             throw new \RuntimeException(
                 "The standard \"{$this->standard}\" is not installed in PHPCS."
             );