docs: Add troubleshooting for WinUI

[MartinZikmund]

Fixes: #269

PR Type

What kind of change does this PR introduce?

• Documentation content changes

What is the current behavior?

What is the new behavior?

PR Checklist

Please check if your PR fulfills the following requirements:

• [ ] Tested code with current supported SDKs
• [x] Docs have been added/updated which fit documentation template. (for bug fixes / features)
• [ ] Unit Tests and/or UI Tests for the changes have been added (for bug fixes / features) (if applicable)
• [ ] Wasm UI Tests are not showing unexpected any differences. Validate PR Screenshots Compare Test Run results.
• [ ] Contains NO breaking changes
• [ ] Updated the Release Notes
• [ ] Associated with an issue (GitHub or internal)

Other information

Internal Issue (If applicable):

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