title: Chart.js draw y-axis only up to point
body: <p>I'm wondering how to draw the y-axis only up to the point of one dataset. Like in this example: </p>
  
  <p><a href="https://i.stack.imgur.com/dwxzY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dwxzY.png" alt="enter image description here"></a></p>
  
  <p>So far I've tried a hacky version by adding an inversed white background on the dataset, but because I have some offset on the x-axis the white background cuts suddently, and the Y-axis lines becomes hidden.</p>
  
  <p>Does anyone know how to loop through each grid line and give it the correct length?</p>