Integrate new funnel step query

[EDsCODE]

Is your feature request related to a problem?

Please describe.
Right now, we're using the built in clickhouse windowFunnel function. This has done us well but as we move on to implement more features such as funnel conversion time averages, we'll need more ability to see the underlying events related to each user funnel

Describe the solution you'd like

Implement the new query that's written on metabase.

Additional context

One part of this will be slightly tricky as you need to figure out how to repeat the logic that enables us to ensure we're always choosing a later event. The query does this from step_2 to step_3, but we'll need to guarantee this for step_x to step_(x+1)

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[EDsCODE]

Query here: https://metabase.posthog.net/question/78