## Bug description

*Please describe.*  
*If this affects the front-end, screenshots would be of great help.*  

funnels -> select two steps for the funnel -> historical view

This is because we're not passing in a year to dayjs so it defaults to 2001

<img width="592" alt="Screen Shot 2021-07-14 at 1 39 47 PM" src="https://user-images.githubusercontent.com/25164963/125667575-5f8c2450-5998-4602-8a36-f886c1c786c5.png">


## Expected behavior



## How to reproduce

1.
2.
3.

## Environment

- [ ] PostHog Cloud
- [ ] self-hosted PostHog, version/commit: _please provide_

## Additional context



#### *Thank you* for your bug report – we love squashing them!

ee/clickhouse/queries/funnels/funnel_trends.py
"""
    ## Funnel trends assumptions
    Funnel trends are a graph of conversion over time – meaning a Y ({conversion_rate}) for each X ({entrance_period}).
    ### What is {entrance_period}?
    A funnel is considered entered by a user when they have performed its first step.
    When that happens, we consider that an entrance of funnel.
    Now, our time series is based on a sequence of {entrance_period}s, each starting at {entrance_period_start}
    and ending _right before the next_ {entrance_period_start}. A person is then counted at most once in each
    {entrance_period}.
    ### What is {conversion_rate}?
    Each time a funnel is entered by a person, they have exactly {funnel_window_days} days to go
    through the funnel's steps. Later events are just not taken into account.
    For {conversion_rate}, we need to know reference steps: {from_step} and {to_step}.
    By default they are respectively the first and the last steps of the funnel.
    Then for each {entrance_period} we calculate {reached_from_step_count} – the number of persons
    who entered the funnel and reached step {from_step} (along with all the steps leading up to it, if there any).
    Similarly we calculate {reached_to_step_count}, which is the number of persons from {reached_from_step_count}
    who also reached step {to_step} (along with all the steps leading up to it, including of course step {from_step}).
    {conversion_rate} is simply {reached_to_step_count} divided by {reached_from_step_count},
    multiplied by 100 to be a percentage.
    If no people have reached step {from_step} in the period, {conversion_rate} is zero.
    """
    def __init__(