Add 'WHEN' Condition for UPDATE Webhooks in UI

Currently, when creating a database webhook for UPDATE events through the Supabase UI, there isn't an option to specify a conditional WHEN clause.

This limitation causes an issue when an Edge Function is triggered by a row update and subsequently modifies a column in that same row. This modification re-triggers the UPDATE webhook, leading to an infinite loop or unnecessary function executions.

While it's possible to add a WHEN clause using SQL to prevent this (e.g., WHEN (old.* IS DISTINCT FROM new.*) on specific columns), this functionality is missing from the dashboard UI