## Bug description
I added an event (that exists) to an action, and now my action hangs forever.

I added an insight viewed event

w/ filters `insight == RETENTION` and `same_retention_and_cohortizing_event = false` – this appears to have broken my action where it does not load and I cannot edit it.

Cannot reproduce this same behavior locally.


## Expected behavior
- The action loads if the schema is correct.
-  If there's erroneous data it should load and let me edit it.

## How to reproduce

1. Create an action on Posthog cloud, in our main app
2. Add 'insight viewed' with filters `insight == RETENTION` and `same_retention_and_cohortizing_event = false`
3. The action will spin forever

## Environment

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

## Additional context

[Sentry error](https://sentry.io/organizations/posthog/issues/2378948964/?project=1899813&referrer=slack)

Console errors 
<img width="1607" alt="Screen Shot 2021-05-03 at 5 45 39 PM" src="https://user-images.githubusercontent.com/5965891/116950024-b0d7a280-ac38-11eb-93c8-245390240532.png">
<img width="1167" alt="Screen Shot 2021-05-03 at 5 51 34 PM" src="https://user-images.githubusercontent.com/5965891/116950026-b208cf80-ac38-11eb-96e1-6a8f018f650a.png">



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

ee/clickhouse/models/property.py
import re
from typing import Any, Dict, List, Optional, Tuple
from django.conf import settings
from django.utils import timezone
from ee.clickhouse.client import sync_execute
from ee.clickhouse.models.cohort import format_filter_query
from ee.clickhouse.models.util import is_int, is_json
from ee.clickhouse.sql.events import SELECT_PROP_VALUES_SQL, SELECT_PROP_VALUES_SQL_WITH_FILTER
from ee.clickhouse.sql.person import GET_DISTINCT_IDS_BY_PROPERTY_SQL, GET_LATEST_PERSON_DISTINCT_ID_SQL
from posthog.models.cohort import Cohort
from posthog.models.event import Selector
from posthog.models.property import Property
from posthog.models.team import Team
from posthog.utils import is_valid_regex, relative_date_parse
def parse_prop_clauses(