fix: Updated UWP Samples app signing certificate

[MartinZikmund]

GitHub Issue (If applicable): #3022

PR Type

What kind of change does this PR introduce?

• Bugfix

What is the current behavior?

Temp signing certificate for UWP is expired

What is the new behavior?

Replaced temp signing certificate

PR Checklist

Please check if your PR fulfills the following requirements:

• 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)
• Validated PR Screenshots Compare Test Run results.
• Contains NO breaking changes
• Associated with an issue (GitHub or internal) and uses the automatic close keywords.
• Commits must be following the Conventional Commits specification.

[gitpod-io]

[jeromelaban]

Thanks Martin!