## 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
if not data:
            raise RequestParsingError("Failed to decompress data.")
        data = data.encode("utf-16", "surrogatepass").decode("utf-16")
    base64_decoded = None
    try:
        base64_decoded = base64_decode(data)
        KLUDGES_COUNTER.labels(kludge="base64_after_decompression_" + compression).inc()
    except Exception:
        pass
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        data = base64_decoded
    try:
        
        
        
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    except (json.JSONDecodeError, UnicodeDecodeError) as error_main:
        if compression == "":
            try:
                fallback = decompress(data, "gzip")
                KLUDGES_COUNTER.labels(kludge="unspecified_gzip_fallback").inc()
                return fallback
            except Exception as inner:
                
                raise RequestParsingError("Invalid JSON: %s" % (str(error_main))) from inner
        else:
            raise RequestParsingError("Invalid JSON: %s" % (str(error_main)))
    
    return data
def load_data_from_request(request):