title: Increase distance between text and title on the y-axis
body: <p>The y-axis title appears too close to the axis text.</p>
  
  <pre><code>ggplot(mpg, aes(cty, hwy)) + geom_point()
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/21mFn.png" alt="ggplot output"></p>
  
  <p>I have tried changing the value of many parameters with <code>theme()</code> but none seems to help.</p>