Bump FluentAssertions from 6.4.0 to 6.5.1

Bumps [FluentAssertions](https://github.com/fluentassertions/fluentassertions) from 6.4.0 to 6.5.1.
- [Release notes](https://github.com/fluentassertions/fluentassertions/releases)
- [Changelog](https://github.com/fluentassertions/fluentassertions/blob/develop/AcceptApiChanges.ps1)
- [Commits](fluentassertions/fluentassertions@6.4.0...6.5.1)

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

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

Tests/Serilog.Exceptions.Test/Serilog.Exceptions.Test.csproj

@@ -16,7 +16,7 @@
   </ItemGroup>
 
   <ItemGroup Label="Package References">
-    <PackageReference Include="FluentAssertions" Version="6.4.0" />
+    <PackageReference Include="FluentAssertions" Version="6.5.1" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
   </ItemGroup>