## Bug description

The grouped-by-month view in charts is hella confusing. The x-axis shows a date that does not reflect the value on the y-axis.

1. the y-axis shows the number for the END of the month
2. the x-axis reads as "beginning of the month"

![CleanShot 2024-02-05 at 10 23 30@2x](https://github.com/PostHog/posthog/assets/35429197/d78df745-8319-4b78-95fa-d96f18aee357)

### Comparison with daily grouping

Compare the "group by month" view with "group by day". The x-axis labeling aligns with the y-axis values. 

![CleanShot 2024-02-05 at 10 29 20@2x](https://github.com/PostHog/posthog/assets/35429197/998825fa-7406-4214-8310-8f173980f80c)


## How to reproduce

1. Group a chart by month 
2. select "unique events"

## Proposal 

### 1. easy fix - remove the "1." from the labelling

- will still confuse readers with "is this the beginning or end of the month"

![CleanShot 2024-02-05 at 10 23 30@2x](https://github.com/PostHog/posthog/assets/35429197/1a0ae6d4-0e02-4b32-86ab-7b0e069655ed)

### 2. correct fix - show end of month

- removes ambiguity from "is that the beginning or end of month"
- harder to implement because months have different end days

![CleanShot 2024-02-05 at 10 23 30@2x](https://github.com/PostHog/posthog/assets/35429197/61226346-7f97-4bcd-87bf-53fc83c75245)


cc @jannesblobel
posthog/hogql_queries/insights/lifecycle_query_runner.py
with self.timings.measure("events_query"):
            events_query = parse_select(
                """
                    SELECT
                        events.person.id as person_id,
                        min(events.person.created_at) AS created_at,
                        arraySort(groupUniqArray({trunc_timestamp})) AS all_activity,
                        arrayPopBack(arrayPushFront(all_activity, {trunc_created_at})) as previous_activity,
                        arrayPopFront(arrayPushBack(all_activity, {trunc_epoch})) as following_activity,
                        arrayMap((previous, current, index) -> (previous = current ? 'new' : ((current - {one_interval_period}) = previous AND index != 1) ? 'returning' : 'resurrecting'), previous_activity, all_activity, arrayEnumerate(all_activity)) as initial_status,
                        arrayMap((current, next) -> (current + {one_interval_period} = next ? '' : 'dormant'), all_activity, following_activity) as dormant_status,
                        arrayMap(x -> x + {one_interval_period}, arrayFilter((current, is_dormant) -> is_dormant = 'dormant', all_activity, dormant_status)) as dormant_periods,
                        arrayMap(x -> 'dormant', dormant_periods) as dormant_label,