Bump FluentAssertions from 6.11.0 to 6.12.0 in /csharp

Bumps [FluentAssertions](https://github.com/fluentassertions/fluentassertions) from 6.11.0 to 6.12.0.
- [Release notes](https://github.com/fluentassertions/fluentassertions/releases)
- [Changelog](https://github.com/fluentassertions/fluentassertions/blob/develop/AcceptApiChanges.ps1)
- [Commits](fluentassertions/fluentassertions@6.11.0...6.12.0)

---
updated-dependencies:
- dependency-name: FluentAssertions
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

csharp/tests/Murex/Kata/BowlingGame/BowlingGame.Tests.csproj

@@ -10,7 +10,7 @@
 
     <ItemGroup>
         <PackageReference Include="JunitXml.TestLogger" Version="3.0.134" />
-        <PackageReference Include="FluentAssertions" Version="6.11.0" />
+        <PackageReference Include="FluentAssertions" Version="6.12.0" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.7.1" />
         <PackageReference Include="xunit" Version="2.5.0" />
         <PackageReference Include="xunit.runner.visualstudio" Version="2.5.0">