## Bug description

<img width="696" alt="Screen Shot 2021-09-16 at 2 37 41 PM" src="https://user-images.githubusercontent.com/13460330/133689529-c4fffc7f-53f8-494e-b7a8-7fb656fd50e6.png">

## Expected behavior

Bars and labels always show on top of axes and gridlines.

## How to reproduce

1. https://app.posthog.com/insights?insight=FUNNELS&properties=%5B%5D&filter_test_accounts=false&events=%5B%7B%22id%22%3A%22%24pageview%22%2C%22name%22%3A%22%24pageview%22%2C%22type%22%3A%22events%22%2C%22order%22%3A0%7D%2C%7B%22id%22%3A%22%24pageview%22%2C%22name%22%3A%22%24pageview%22%2C%22type%22%3A%22events%22%2C%22order%22%3A1%7D%2C%7B%22id%22%3A%22%24pageview%22%2C%22name%22%3A%22%24pageview%22%2C%22type%22%3A%22events%22%2C%22order%22%3A2%7D%5D&actions=%5B%5D&exclusions=%5B%5D&interval=day&funnel_from_step=0&funnel_to_step=1&new_entity=%5B%5D&funnel_viz_type=time_to_convert&display=FunnelViz

## Environment

- [X] PostHog Cloud
- [X] self-hosted PostHog (ClickHouse-based), version/commit: _please provide_
- [X] self-hosted PostHog (Postgres-based, legacy), version/commit: _please provide_

## Additional context



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

ee/clickhouse/queries/funnels/test/test_funnel_time_to_convert.py
import unittest
from uuid import uuid4
from ee.clickhouse.models.event import create_event
from ee.clickhouse.queries.funnels import ClickhouseFunnel, ClickhouseFunnelStrict, ClickhouseFunnelUnordered
from ee.clickhouse.queries.funnels.funnel_time_to_convert import ClickhouseFunnelTimeToConvert
from ee.clickhouse.util import ClickhouseTestMixin
from posthog.constants import INSIGHT_FUNNELS, TRENDS_LINEAR
from posthog.models.filters import Filter
from posthog.models.person import Person
from posthog.test.base import APIBaseTest
FORMAT_TIME = "%Y-%m-%d %H:%M:%S"
FORMAT_TIME_DAY_END = "%Y-%m-%d 23:59:59"
def _create_person(**kwargs):
    person = Person.objects.create(**kwargs)
    return Person(id=person.uuid, uuid=person.uuid)
def _create_event(**kwargs):
    kwargs.update({"event_uuid": uuid4()})
    create_event(**kwargs)
class TestFunnelTrends(ClickhouseTestMixin, APIBaseTest):