## Problem
#44677 modified the previous behaviour on callback URLs. It used to
prevent users to remove the URL if only one was provided.
## Solution
Restore the previous behaviour.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Bug Fixes**
* Fixed the Remove button behavior for OAuth callback URLs. The button
now only appears when multiple callback URLs are configured, preventing
accidental deletion of the only redirect URI.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Gildas Garcia
054e44f7e6