fix(flags): Defend against invalid data on creation

[neilkakkar]

Problem

... and don't put db down on dataErrors

Fixes https://posthog.sentry.io/issues/5214119968/?project=1899813&referrer=slack and https://posthog.sentry.io/issues/5250370222/?query=DataError&referrer=issue-stream&statsPeriod=24h&stream_index=0

Changes

👉 Stay up-to-date with PostHog coding conventions for a smoother review.

Does this work well for both Cloud and self-hosted?

How did you test this code?

[sentry-io]

Suspect Issues

This pull request was deployed and Sentry observed the following issues:

• ‼️ AttributeError: 'list' object has no attribute 'get' /api/projects/{parent_lookup_team_id}/surveys/{... View Issue

_{Did you find this useful? React with a 👍 or 👎}