remove redundant sort call on points

Created by: unclejustin

Closes https://github.com/sourcegraph/sourcegraph/issues/34250

https://user-images.githubusercontent.com/1855233/171300543-058dbc24-7e4a-42a5-a18c-385d2f028734.mov

Test plan

• Existing tests and screenshot checks should still pass
• Go to any insight with overlapping data series
• Hover should still render line and points above others

App preview:

• Web
• Storybook

Check out the client app preview documentation to learn more.