Update .NET packages to v9 (#1383)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

Directory.Packages.props

@@ -27,11 +27,11 @@
     <PackageVersion Include="Microsoft.Windows.SDK.Win32Metadata" Version="$(MetadataVersion)" />
     <PackageVersion Include="Microsoft.Windows.WDK.Win32Metadata" Version="$(WDKMetadataVersion)" />
     <PackageVersion Include="NuGet.Protocol" Version="6.13.2" />
-    <PackageVersion Include="System.Collections.Immutable" Version="8.0.0" />
+    <PackageVersion Include="System.Collections.Immutable" Version="9.0.0" />
     <PackageVersion Include="System.Memory" Version="4.6.0" />
-    <PackageVersion Include="System.Reflection.Metadata" Version="8.0.1" />
+    <PackageVersion Include="System.Reflection.Metadata" Version="9.0.0" />
     <PackageVersion Include="System.Runtime.CompilerServices.Unsafe" Version="6.1.0" />
-    <PackageVersion Include="System.Text.Json" Version="8.0.5" />
+    <PackageVersion Include="System.Text.Json" Version="9.0.0" />
     <PackageVersion Include="Xunit.Combinatorial" Version="2.0.24" />
     <PackageVersion Include="Xunit.Assert" Version="2.9.3" />
   </ItemGroup>