Bump .NET NuGet packages

Bumps .NET dependencies to their latest versions for the .NET 9.0.100-preview.2.24157.14 SDK.

Bumps Microsoft.AspNetCore.Mvc.Testing from 9.0.0-preview.1.24081.5 to 9.0.0-preview.2.24128.4.
Bumps Microsoft.AspNetCore.TestHost from 9.0.0-preview.1.24081.5 to 9.0.0-preview.2.24128.4.

---
updated-dependencies:
- dependency-name: Microsoft.AspNetCore.Mvc.Testing
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: Microsoft.AspNetCore.TestHost
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: aspnet-contrib-service-account[bot] <161750942+aspnet-contrib-service-account[bot]@users.noreply.github.com>

Author: aspnet-contrib-service-account[bot]

Directory.Packages.props

@@ -5,8 +5,8 @@
     <PackageVersion Include="JetBrains.Annotations" Version="2023.3.0" />
     <PackageVersion Include="JustEat.HttpClientInterception" Version="4.2.0" />
     <PackageVersion Include="MartinCostello.Logging.XUnit" Version="0.3.0" />
-    <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="9.0.0-preview.1.24081.5" />
-    <PackageVersion Include="Microsoft.AspNetCore.TestHost" Version="9.0.0-preview.1.24081.5" />
+    <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="9.0.0-preview.2.24128.4" />
+    <PackageVersion Include="Microsoft.AspNetCore.TestHost" Version="9.0.0-preview.2.24128.4" />
     <PackageVersion Include="Microsoft.IdentityModel.Protocols" Version="7.0.3" />
     <PackageVersion Include="Shouldly" Version="4.2.1" />
   </ItemGroup>