title: Horizontal UIStackView inside UIScrollView not scrolling
body: <p>I have a horizontal UIStackView with 3 buttons inside UIScrollView. I'd like the stack to scroll horizontally when the user changes the font size (via Accessibility).</p>
  
  <p><a href="https://i.stack.imgur.com/aL34v.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/aL34v.png" alt="Storyboard"></a></p>
  
  <p>Right now, when the user increases the font size, one of the buttons gets squashed.</p>
  
  <p>Here are my constraints:</p>
  
  <p><a href="https://i.stack.imgur.com/curgG.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/curgG.png" alt="UIStackView constraints"></a>  </p>
  
  <p><a href="https://i.stack.imgur.com/dYm33.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dYm33.png" alt="UIScrollView constraints"></a></p>