chore: Bump FluentAssertions from 7.2.0 to 8.8.0

---
updated-dependencies:
- dependency-name: FluentAssertions
  dependency-version: 8.8.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

tests/Auth0.AspNetCore.Authentication.Api.UnitTests/Auth0.AspNetCore.Authentication.Api.UnitTests.csproj

@@ -11,7 +11,7 @@
 
     <ItemGroup>
         <!-- Using v7.2.0 as it's the last version with Apache license. Newer versions use different licensing -->
-        <PackageReference Include="FluentAssertions" Version="7.2.0"/>
+        <PackageReference Include="FluentAssertions" Version="8.8.0"/>
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0"/>
         <PackageReference Include="Moq" Version="4.20.72"/>
         <PackageReference Include="xunit" Version="2.9.3"/>