chore(deps): update dependency microsoft.windowsappsdk to 1.6.250228001 (#3999)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
|
[Microsoft.WindowsAppSDK](https://redirect.github.com/microsoft/windowsappsdk)
| `1.6.250205002` -> `1.6.250228001` |
[![age](https://developer.mend.io/api/mc/badges/age/nuget/Microsoft.WindowsAppSDK/1.6.250228001?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/nuget/Microsoft.WindowsAppSDK/1.6.250228001?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/nuget/Microsoft.WindowsAppSDK/1.6.250205002/1.6.250228001?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
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|

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src/Directory.Packages.props

@@ -47,7 +47,7 @@
     <PackageVersion Include="Xamarin.AndroidX.Lifecycle.LiveData" Version="$(XamarinAndroidXLifecycleLiveDataVersion)" />
   </ItemGroup>
   <ItemGroup Condition="'$(UseMaui)' != 'true'">
-    <PackageVersion Include="Microsoft.WindowsAppSDK" Version="1.6.250205002" />
+    <PackageVersion Include="Microsoft.WindowsAppSDK" Version="1.6.250228001" />
   </ItemGroup>
   <ItemGroup Condition="$(TargetFramework.StartsWith('net4'))">
     <PackageVersion Include="System.ValueTuple" Version="4.5.0" />