Bump FluentAssertions from 7.0.0 to 8.0.0

Bumps [FluentAssertions](https://github.com/fluentassertions/fluentassertions) from 7.0.0 to 8.0.0.
- [Release notes](https://github.com/fluentassertions/fluentassertions/releases)
- [Changelog](https://github.com/fluentassertions/fluentassertions/blob/develop/AcceptApiChanges.ps1)
- [Commits](fluentassertions/fluentassertions@7.0.0...8.0.0)

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

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

Author: dependabot[bot]

Tests/Directory.Packages.props

@@ -4,7 +4,7 @@
     <CentralPackageTransitivePinningEnabled>true</CentralPackageTransitivePinningEnabled>
   </PropertyGroup>
   <ItemGroup>
-    <PackageVersion Include="FluentAssertions" Version="7.0.0" />
+    <PackageVersion Include="FluentAssertions" Version="8.0.0" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="9.0.0" />
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageVersion Include="NSubstitute" Version="5.3.0" />