## Is your feature request related to a problem?

Currently the funnel time to convert query (added in #4947) only allows measuring time it took to a specific step from the one immediately preceding it. However it'd be useful to also bin by the _total_ time to convert – how long it took to complete the funnel (reach the last step) from entering it (reaching the first step).

## Describe the solution you'd like

Right now `ClickhouseFunnelTimeToConvert` uses only `Filter.funnel_to_step`. It should also be able to work with `Filter.funnel_from_step`. If `funnel_from_step` is `0` and `funnel_to_step` is `len(steps)-1`, that'd be the total time to convert.

#### *Thank you* for your feature request – we love each and every one!

ee/clickhouse/queries/funnels/funnel_time_to_convert.py
( SELECT bin_width_seconds FROM histogram_params ) AS bin_width_seconds,
                -- bin_count is only made available as an identifier if it had to be calculated
                {
                    f"( SELECT {bin_count_identifier} FROM histogram_params ) AS {bin_count_identifier},"
                    if bin_count_expression else ""
                }
                ( SELECT from_seconds FROM histogram_params ) AS histogram_from_seconds,
                ( SELECT to_seconds FROM histogram_params ) AS histogram_to_seconds
            SELECT
                bin_to_seconds,
                person_count
            FROM (
                -- Calculating bins from step runs
                SELECT
                    histogram_from_seconds + floor((step_{to_step}_average_conversion_time - histogram_from_seconds) / bin_width_seconds) * bin_width_seconds AS bin_to_seconds,
                    count() AS person_count
                FROM step_runs
                WHERE step_{to_step}_average_conversion_time IS NOT NULL
                GROUP BY bin_to_seconds
            ) results
            FULL OUTER JOIN (
                -- Making sure bin_count bins are returned
                -- Those not present in the results query due to lack of data simply get person_count 0
                SELECT histogram_from_seconds + number * bin_width_seconds AS bin_to_seconds FROM system.numbers LIMIT {bin_count_identifier} + 1
            ) fill
            USING (bin_to_seconds)
            ORDER BY bin_to_seconds
            SETTINGS allow_experimental_window_functions = 1"""
        return query