How to update Custom Map geojson endpoint

I am trying to fix an issue with a custom map endpoint being HTTP rather than HTTPS. The page freezes when I select any custom map so I can’t update the URL through the UI. I am attempting to find the URLs in the db to update them, but haven’t been able to find where its stored yet.

Just for reference for others:
https://github.com/metabase/metabase/issues/12597