## Bug description

There seems to be an issue with `get_available_timezones_with_offsets`, not sure at what point it broke.

```
Traceback (most recent call last):
    response = view_func(request, *args, **kwargs)
  File "/posthog/posthog/views.py", line 184, in preflight_check
    "available_timezones": get_available_timezones_with_offsets(),
    raise NonExistentTimeError(dt)
```

## Expected behavior
Preflight should work and the timezone list be returned correctly.


## How to reproduce

1. Just check `/_preflight` request

## Environment

- [X] PostHog Cloud
- [ ] self-hosted PostHog, version/commit: _please provide_

## Additional context

Tagging @Twixes as you have more context on this.

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

posthog/utils.py
append: Dict[str, Any] = {}
    append["data"] = []
    append["labels"] = []
    append["days"] = []
    days_format = "%Y-%m-%d"
    if interval == "hour" or interval == "minute":
        days_format += " %H:%M:%S"
    for item in dates_filled:
        date = item[0]
        value = item[1]
        append["days"].append(date.strftime(days_format))
        append["labels"].append(format_label_date(date, interval))
        append["data"].append(value)
    if math == "sum":
        append["count"] = sum(append["data"])
    return append
def get_ip_address(request: HttpRequest) -> str:
    """ use requestobject to fetch client machine's IP Address """
    x_forwarded_for = request.META.get("HTTP_X_FORWARDED_FOR")
    if x_forwarded_for:
        ip = x_forwarded_for.split(",")[0]
    else:
        ip = request.META.get("REMOTE_ADDR")  
    return ip
def dict_from_cursor_fetchall(cursor):