title: CascadeMode StopOnFirstFailure doesn't work
body: <pre><code>public class Validator : AbstractValidator&lt;Query&gt;
          {
              public Validator()
              {
                  CascadeMode = CascadeMode.StopOnFirstFailure;
  
                  RuleFor(x =&gt; x.A).NotEmpty();
                  RuleFor(x =&gt; x.B).NotEmpty();
                  RuleFor(x =&gt; x).MustAsync(...);
              }
          }
  </code></pre>
  
  <p>I'like to construct validator which dones't call <code>MustAsync</code> when above rules are not met. Unfortunately settings <code>CascadeMode</code> to <code>StopOnFirstFailure</code>  in validator doesn't do the work.</p>