Using Step interpolation on Series of line plot causes line to go beyond canvas grid

[binyata]

[binyata]

Sample code that uses step interpolation:
let priceSeries = chart.addSeries(['product_id', 'retailer'], dimple.plot.line, [dateAxis, priceAxis]);
priceSeries.getTooltipText = seriesTooltipText('Price');
priceSeries.interpolation = 'step';