Compare to previous period for each breakdown

[MarconLP]

Feature request

Is your feature request related to a problem?

It's not possible to view the difference compared to the previous period when breaking down the insight.

Additional context

https://posthoghelp.zendesk.com/agent/tickets/13284

Debug info

Session: https://us.posthog.com/project/sTMFPsFhdP1Ssg/replay/018f5e79-11fa-76a5-af20-b6b5b143ae57?t=0 
Admin: http://go/adminOrgEU/01898c01-032f-0000-77bd-be3f4ddf024e (Project: 7347)
Sentry: http://go/sentryEU/7347

[aspicer]

From @MarconLP:

Currently we just show two rows, one for current and one for previous, and it's very hard to compare.