Resolve #3238915 "Refactor if feasible"

Closes #3238915

core/lib/Drupal/Core/Security/RequestSanitizer.php

@@ -21,15 +21,6 @@ class RequestSanitizer {
    */
   const SANITIZE_INPUT_SAFE_KEYS = 'sanitize_input_safe_keys';
 
-  /**
-   * Previous name of SANITIZE_INPUT_SAFE_KEYS.
-   *
-   * @deprecated in drupal:9.1.0 and is removed from drupal:10.0.0. Use
-   *   SANITIZE_INPUT_SAFE_KEYS instead.
-   * @see https://www.drupal.org/node/3163148
-   */
-  const SANITIZE_WHITELIST = 'sanitize_input_whitelist';
-
   /**
    * The name of the setting that determines if sanitized keys are logged.
    */