danger: Add a check for changing Collab database schemas (#51234)

This PR adds a Danger check to remind contributors that any database
changes for Collab need to be done via a migration in the Cloud repo:

<img width="888" height="323" alt="Screenshot 2026-03-10 at 6 39 21 PM"
src="https://github.com/user-attachments/assets/5b3bbc3d-1e9d-409a-837b-565e1ca36935"
/>

Release Notes:

- N/A
7bf73098a7Marshall Bowers committed on 3/10/2026, 10:53:38 PM· committed by GitHubparent51ba321
1 file changedLine totals unavailable