Dashboard precheck blocks the change of other PD configurations

## Bug Report

If the dashboard uses an old PD address, which could have been offline already, the pd server config cannot be changed due to the precheck. One workaround is to disable the dashboard first before making the change.

<img width="2336" height="194" alt="Image" src="https://github.com/user-attachments/assets/68098eb2-0f35-4658-8329-ad4ff4caaf40" />
