Bump FluentAssertions from 6.11.0 to 8.7.1#9

dependabot[bot] wants to merge 1 commit intodevelopfgrzl/gravel:developfrom

dependabot/nuget/test/Gravel.Tests/FluentAssertions-8.7.1fgrzl/gravel:dependabot/nuget/test/Gravel.Tests/FluentAssertions-8.7.1Copy head branch name to clipboard