Bump FluentAssertions from 6.11.0 to 6.12.0

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>

Author: dependabot[bot]

test/TestBuildingBlocks/TestBuildingBlocks.csproj

@@ -11,7 +11,7 @@
     <PackageReference Include="Bogus" Version="34.0.2" />
     <PackageReference Include="coverlet.collector" Version="$(CoverletVersion)" PrivateAssets="All" />
     <PackageReference Include="GitHubActionsTestLogger" Version="$(GitHubActionsTestLoggerVersion)" PrivateAssets="All" />
-    <PackageReference Include="FluentAssertions" Version="6.11.0" />
+    <PackageReference Include="FluentAssertions" Version="6.12.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="$(AspNetVersion)" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Relational" Version="$(EFCoreVersion)" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="$(TestSdkVersion)" />