[13.x] Add UnitEnum type support for $limiterName on RateLimitedWithRedis

[trippo]

Add UnitEnum type support to the $limiterName PHPDoc in the RateLimitedWithRedis constructor to match the parent RateLimited implementation and improve consistency.

/**
     * Create a new middleware instance.
     *
     * @param  \UnitEnum|string  $limiterName
     */
    public function __construct($limiterName)
    {