Bump Microsoft.NETCore.UniversalWindowsPlatform from 6.1.5 to 6.2.8

Bumps [Microsoft.NETCore.UniversalWindowsPlatform](https://github.com/Microsoft/dotnet) from 6.1.5 to 6.2.8.
- [Release notes](https://github.com/Microsoft/dotnet/releases)
- [Commits](https://github.com/Microsoft/dotnet/commits)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

ZeroconfTest.UWP/ZeroconfTest.UWP.csproj

@@ -137,7 +137,7 @@
       <Project>{493b9f32-83fa-4b6e-ad59-c071bab47229}</Project>
       <Name>Zeroconf</Name>
     </ProjectReference>
-    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="6.1.5" />
+    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="6.2.8" />
   </ItemGroup>
   <PropertyGroup Condition=" '$(VisualStudioVersion)' == '' or '$(VisualStudioVersion)' &lt; '14.0' ">
     <VisualStudioVersion>14.0</VisualStudioVersion>