## 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
template_name: str,
    request: HttpRequest,
    context: Dict = {},
    *,
    team_for_public_context: Optional["Team"] = None,
) -> HttpResponse:
    """Render Django template.
    If team_for_public_context is provided, this means this is a public page such as a shared dashboard.
    """
    template = get_template(template_name)
    context["opt_out_capture"] = settings.OPT_OUT_CAPTURE
    context["self_capture"] = settings.SELF_CAPTURE
    context["region"] = get_instance_region()
    if sentry_dsn := os.environ.get("SENTRY_DSN"):
        context["sentry_dsn"] = sentry_dsn
    if sentry_environment := os.environ.get("SENTRY_ENVIRONMENT"):
        context["sentry_environment"] = sentry_environment
    context["git_rev"] = get_git_commit()  
    if settings.DEBUG and not settings.TEST:
        context["debug"] = True
        context["git_branch"] = get_git_branch()
    if settings.E2E_TESTING:
        context["e2e_testing"] = True
        context["js_posthog_api_key"] = "'phc_ex7Mnvi4DqeB6xSQoXU1UVPzAmUIpiciRKQQXGGTYQO'"
        context["js_posthog_host"] = "'https://app.posthog.com'"
    elif settings.SELF_CAPTURE:
        api_token = get_self_capture_api_token(request)
        if api_token: