Rollback to button unresponsive after successful api request

[dancrew32]

When clicking this button, the rollback procedure kicks off successfully, but the UI does not reflect that anything has succeeded. This can cause a train engineer to hit the button multiple times, which may cause issues.

https://github.com/Nextdoor/conductor/blob/92d83a355efadc443e0cf01f7493c04454adffde/frontend/src/components/Summary.jsx#L339-L354