Bump Microsoft.NET.Test.Sdk from 16.9.1 to 16.9.4 in /Ix.NET/Source

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 16.9.1 to 16.9.4.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Commits](https://github.com/microsoft/vstest/compare/v16.9.1...v16.9.4)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Ix.NET/Source/System.Interactive.Async.Providers.Tests/System.Interactive.Async.Providers.Tests.csproj

@@ -17,7 +17,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

Ix.NET/Source/System.Interactive.Async.Tests/System.Interactive.Async.Tests.csproj

@@ -17,7 +17,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
     <PackageReference Include="FluentAssertions" Version="5.10.3" />
     <PackageReference Include="xunit" Version="2.4.1" />

Ix.NET/Source/System.Interactive.Tests/System.Interactive.Tests.csproj

@@ -16,7 +16,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

Ix.NET/Source/System.Linq.Async.Queryable.Tests/System.Linq.Async.Queryable.Tests.csproj

@@ -17,7 +17,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
     <PackageReference Include="FluentAssertions" Version="5.10.3" />
     <PackageReference Include="xunit" Version="2.4.1" />

Ix.NET/Source/System.Linq.Async.Tests/System.Linq.Async.Tests.csproj

@@ -39,7 +39,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
     <PackageReference Include="FluentAssertions" Version="5.10.3" />
     <PackageReference Include="xunit" Version="2.4.1" />