title: UIButton titleLabel has padding
body: <p><code>UIButton</code> title label has top and bottom padding, I want to remove padding.
  Set <code>UIButton</code>  content mode did not work.</p>
  <p>Here is my code</p>
  <pre><code>    lazy var button: UIButton = {
          let button = UIButton(type: .custom)
          button.translatesAutoresizingMaskIntoConstraints = false
          button.setTitleColor(ThemeColor.red, for: .normal)
          button.setTitle(&quot;Push&quot;, for: .normal)
          button.addTarget(self, action: #selector(buttonDidTap), for: .touchUpInside)
          button.backgroundColor = .blue
          button.contentHorizontalAlignment = .fill
          button.contentVerticalAlignment = .fill
          button.contentMode = .scaleAspectFill
          return button
      }()
  </code></pre>
  <p>and it looks like
  <a href="https://i.stack.imgur.com/Jgd2u.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Jgd2u.jpg" alt="enter image description here" /></a></p>
  <p>How can I remove the padding space!</p>