## 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/utils.py
from posthog.models import Team
    
    team: Optional[Team] = None
    if request and getattr(request, "user", None) and getattr(request.user, "team", None):
        team = request.user.team  
    else:
        try:
            team = Team.objects.only("api_token").first()
        except Exception:
            pass
    if team:
        return team.api_token
    return None
def get_default_event_name(team: "Team"):
    from posthog.models import EventDefinition
    if EventDefinition.objects.filter(team=team, name="$pageview").exists():
        return "$pageview"
    elif EventDefinition.objects.filter(team=team, name="$screen").exists():
        return "$screen"
    return "$pageview"
def get_frontend_apps(team_id: int) -> Dict[int, Dict[str, Any]]: