## Bug description

Sites built with Tailwind use a lot of classes like: `text-base leading-6 font-medium text-gray-500 hover:text-gray-900 focus:outline-none focus:text-gray-900 transition ease-in-out duration-150` 

The problem is with the ones that have a colon (`:`) inside them. Simmerjs crashes with the following:

```
Failed to execute 'querySelectorAll' on 'Document': 'A.text-base.leading-6.text-gray-400.hover:text-gray-500.hover:text-white' is not a valid selector
```

... bringing down the entire toolbar.

## Expected behavior

The toolbar shouldn't crash when your page contains a CSS class with a colon in it.

https://stackoverflow.com/questions/45110893/select-elements-by-attributes-with-colon

## How to reproduce

1. Make a page with a `<button />` that has a class `with:colon`.
2. Wait for a few events to be captured or click the button yourself
3. Open the toolbar, click "heatmap" and watch it burst up in flames (and then crash)

posthog/models/event.py
import copy
import datetime
import random
import re
import string
from collections import defaultdict
from typing import Any, Dict, List, Optional, Tuple, Union
import celery
from django.conf import settings
from django.contrib.postgres.fields import JSONField
from django.core.cache import cache
from django.db import connection, models, transaction
from django.db.models import (