title: button.setImage(nil, for: .normal) not working in iOS 15
body: <p>I was trying to make a simple tic-tac-toe app in Swift, so I set up 9 buttons with tags from 1 to 9 and call <code>setImage</code> to set noughts or crosses. This is working as intended.</p>
  <p>The problem comes when trying to reset the board, where I call this piece of code:</p>
  <pre><code>for i in 1..&lt;10 {
      if let button = view.viewWithTag(i) as? UIButton {
          button.setImage(nil, for: .normal)
      }
  }
  </code></pre>
  <p>This should remove the image from the button, but it does nothing. The button is set to <code>Custom</code> in the storyboard, and the tags are indeed assigned as they should. I also tried getting an outlet for one of the buttons and calling <code>setImage(nil, for: .normal)</code> in that one and it didn't work either.</p>
  <p>I even created a new project with just a button where I call <code>setImage</code>, and it is indeed working for non-nil images but not with <code>nil</code> as value.</p>
  <p>Has Apple changed the way of removing images? Another question(<a href="https://stackoverflow.com/questions/69883235/when-button-pressed-button-setimagenil-doesnt-work">When button pressed, button.setImage(nil) doesn&#39;t work</a>) seems to have the same problem, but if I work with <code>isHidden</code> I can no longer click on the buttons, and it should not be the workaround, looks very hacky to me.</p>
  <p>Is this a bug on iOS? Did the implementation change or something?</p>
  <p>Thank you.</p>