Bump System.Threading.Tasks.Dataflow from 8.0.1 to 9.0.0 (#1134)

Bumps [System.Threading.Tasks.Dataflow](https://github.com/dotnet/runtime) from 8.0.1 to 9.0.0.
- [Release notes](https://github.com/dotnet/runtime/releases)
- [Commits](dotnet/runtime@v8.0.1...v9.0.0)

---
updated-dependencies:
- dependency-name: System.Threading.Tasks.Dataflow
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

Directory.Packages.props

@@ -38,7 +38,7 @@
     <PackageVersion Include="System.Runtime.Loader" Version="4.3.0" />
     <PackageVersion Include="System.Security.Cryptography.Xml" Version="4.7.1" />
     <PackageVersion Include="System.Text.Json" Version="8.0.5" />
-    <PackageVersion Include="System.Threading.Tasks.Dataflow" Version="8.0.1" />
+    <PackageVersion Include="System.Threading.Tasks.Dataflow" Version="9.0.0" />
     <PackageVersion Include="Validation" Version="2.5.51" />
     <PackageVersion Include="Xunit.Combinatorial" Version="1.6.24" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="2.8.2" />