Bump Microsoft.Orleans.Client and Microsoft.Orleans.Serialization.Abs…

…tractions

Bumps [Microsoft.Orleans.Client](https://github.com/dotnet/orleans) and [Microsoft.Orleans.Serialization.Abstractions](https://github.com/dotnet/orleans). These dependencies needed to be updated together.

Updates `Microsoft.Orleans.Client` from 7.2.1 to 8.1.0
- [Release notes](https://github.com/dotnet/orleans/releases)
- [Commits](dotnet/orleans@v7.2.1...v8.1.0)

Updates `Microsoft.Orleans.Serialization.Abstractions` from 7.2.1 to 8.1.0
- [Release notes](https://github.com/dotnet/orleans/releases)
- [Commits](dotnet/orleans@v7.2.1...v8.1.0)

---
updated-dependencies:
- dependency-name: Microsoft.Orleans.Client
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: Microsoft.Orleans.Serialization.Abstractions
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

src/Tests/Tests.csproj

@@ -13,7 +13,7 @@
     <PackageReference Include="xunit" Version="2.8.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.1" />
     <PackageReference Include="coverlet.collector" Version="6.0.2" />
-    <PackageReference Include="Microsoft.Orleans.Client" Version="7.2.1" />
+    <PackageReference Include="Microsoft.Orleans.Client" Version="8.1.0" />
     <PackageReference Include="Microsoft.Orleans.Server" Version="7.2.6" />
   </ItemGroup>