Bump FluentAssertions from 7.0.0 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] <[email protected]>

Author: dependabot[bot]

tests/NuGetPackageChecker.Tests/NuGetPackageChecker.Tests.csproj

@@ -10,7 +10,7 @@
     <PackageReference Include="xunit" Version="2.9.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.1" />
     <PackageReference Include="coverlet.collector" Version="6.0.2" />
-    <PackageReference Include="FluentAssertions" Version="7.0.0" />
+    <PackageReference Include="FluentAssertions" Version="8.8.0" />
     <PackageReference Include="Microsoft.Build.Utilities.Core" Version="17.12.6" PrivateAssets="All" />
     <PackageReference Include="NuGet.Versioning" Version="6.12.1" PrivateAssets="All" />
     <PackageReference Include="NuGet.ProjectModel" Version="6.12.1" PrivateAssets="All" />