title: VoiceOver Accessibility accessibilityHint not announced
body: <p>I observed that Voice Over does not announce <code>accessibilityHint</code> some times. </p>
  
  <p><code>button.accessibilityHint = "Plays the song."</code></p>
  
  <p>I have read it somewhere that the <code>accessibilityHint</code> will be ignored by iOS sometimes but i'm not able to find the reference in apple docs <a href="https://developer.apple.com/documentation/objectivec/nsobject/1615093-accessibilityhint" rel="noreferrer">here</a>.</p>
  
  <p>Is this the default behaviour of iOS or i have done it wrong, Please help me to figure out the issue.</p>