[BUG] 400 Bad Request on "Connect CCO Dashboard to your Azure subscription" with USGov tenant

### Pre-requirements

- [x] Reviewed the Deployment guide
- [x] Reviewed the Troubleshooting guide
- [x] Reviewed the YouTube channel
- [x] Reviewed the GitHub Issues list

### What dashboard are you reporting an issue on?

Infrastructure

### What happened?

When trying to connect to a USGov tenant, on the Connect CCO Dashboard to your Azure subscription page, it gives a 400 Bad Request error:

> [DataSource.Error] Web.Contents failed to get contents from 'https://login.windows.net/common/oauth2/token' (400): Bad Request"

### Steps to reproduce

1. Open Power BI template
2. Specify tenant name (xxx.onmicrosoft.com)
3. Specify "us-government" AzureKind
4. On https://management.usgovcloudapi.net/subscriptions screen.
5. Select sign in on Organizational account tab
6. Select https://manage.usgovcloudapi.net/ option for which level
7. Sign In
8. Click Connect
9. On https://graph.microsoft.us/tenant.onmicrosoft.com page
10. Select https://graph.microsoft.us/
11. Sign In
12. Click Connect
13. On CCO Dashboard to your Azure subscription page
14. Sign In
15. Get error

### Additional context

_No response_

Start by reproducing the failure with the Power BI template using AzureKind "us-government" and the listed management, Graph, and login URLs. Trace which connection step requests login.windows.net/common/oauth2/token and compare the expected US Government authentication endpoints. Done means the subscription connection completes without a 400 error for a USGov tenant.

Written by the indexing model from the issue text.