Muzaffar

Add error handling for null return from getServiceAccountName

2

### What should be cleaned up or changed? in the handleLogin function on the [login page](https://github.com/kubeedge/dashboard/blob/main/src/app/login/page.tsx), when the user is null or the service account name cannot be retrieved, the...

### PR Checklist If you have any questions, you can refer to the [Contributing Guide](https://github.com/emqx/MQTTX/blob/main/.github/CONTRIBUTING.md) #### What is the current behavior? Currently, when searching through messages in MQTTX, there is...