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Expected Behavior

When using arrow keys to get to list item, would expect active list item to be in view on the screen.

Actual Behavior

Active list item can end up being off screen but page doesn't scroll down.

URL, screen shot, or Codepen exhibiting the issue

https://storybook.grommet.io/?path=/story/visualizations-list-onclickitem--on-click-item-list

Steps to Reproduce

1. Make window smaller than length of list
2. Tab to List
3. Use arrow keys to move down

Your Environment

• Grommet version: Latest (on stable of storybook)
• Browser Name and version: Chrome
• Operating System and version (desktop or mobile): MacOS