Bump Microsoft.WindowsAppSDK in /src (#70)

Bumps [Microsoft.WindowsAppSDK](https://github.com/microsoft/windowsappsdk) from 1.2.230118.102 to 1.3.230331000.
- [Release notes](https://github.com/microsoft/windowsappsdk/releases)
- [Commits](https://github.com/microsoft/windowsappsdk/commits)

---
updated-dependencies:
- dependency-name: Microsoft.WindowsAppSDK
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

src/ReactiveUI.Uno.WinUI/ReactiveUI.Uno.WinUI.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="MSBuild.Sdk.Extras">
+<Project Sdk="MSBuild.Sdk.Extras">
   <PropertyGroup>
     <TargetFrameworks>netstandard20;MonoAndroid12.0;MonoAndroid12.1;MonoAndroid13.0;Xamarin.iOS10;Xamarin.Mac20;net6.0-android;net6.0-ios;net6.0-macos;net6.0-maccatalyst;net6.0-windows10.0.17763.0;net7.0-android;net7.0-ios;net7.0-macos;net7.0-maccatalyst;net7.0-windows10.0.17763.0</TargetFrameworks>
     <PackageId>ReactiveUI.Uno.WinUI</PackageId>
@@ -36,7 +36,7 @@
   </ItemGroup>
   <ItemGroup Condition=" $(TargetFramework.StartsWith('net6.0-windows10')) or $(TargetFramework.StartsWith('net7.0-windows10')) ">
     <PackageReference Include="Microsoft.Windows.SDK.BuildTools" Version="10.0.22621.755" />
-    <PackageReference Include="Microsoft.WindowsAppSDK" Version="1.2.230118.102" />
+    <PackageReference Include="Microsoft.WindowsAppSDK" Version="1.3.230331000" />
   </ItemGroup>
   <ItemGroup Condition=" $(TargetFramework.StartsWith('netstandard')) ">
     <PackageReference Include="Reactive.Wasm" Version="1.2.2" />