deps(test): update dependency fluentassertions to 8.7.0 (#954)

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This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
|
[FluentAssertions](https://xceed.com/products/unit-testing/fluent-assertions/)
([source](https://redirect.github.com/fluentassertions/fluentassertions))
| `8.6.0` -> `8.7.0` |
[![age](https://developer.mend.io/api/mc/badges/age/nuget/FluentAssertions/8.7.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/nuget/FluentAssertions/8.6.0/8.7.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>fluentassertions/fluentassertions (FluentAssertions)</summary>

###
[`v8.7.0`](https://redirect.github.com/fluentassertions/fluentassertions/releases/tag/8.7.0)

[Compare
Source](https://redirect.github.com/fluentassertions/fluentassertions/compare/8.6.0...8.7.0)

<!-- Release notes generated using configuration in .github/release.yml
at ae620add07cf6666841e568fd3bf8a0733478bb5 -->

#### What's Changed

##### New features

- Added System.Text.Json assertion APIs and BeEquivalentTo support by
[@&#8203;dennisdoomen](https://redirect.github.com/dennisdoomen) in
[#&#8203;3094](https://redirect.github.com/fluentassertions/fluentassertions/pull/3094)

##### Others

- Address a bunch of Qodana issues by
[@&#8203;dennisdoomen](https://redirect.github.com/dennisdoomen) in
[#&#8203;3082](https://redirect.github.com/fluentassertions/fluentassertions/pull/3082)
- Bump actions/checkout from 4 to 5 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;3085](https://redirect.github.com/fluentassertions/fluentassertions/pull/3085)
- Bump JetBrains/qodana-action from 2025.1 to 2025.2 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;3086](https://redirect.github.com/fluentassertions/fluentassertions/pull/3086)
- Bump actions/download-artifact from 4 to 5 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;3087](https://redirect.github.com/fluentassertions/fluentassertions/pull/3087)
- Bump cspell from 9.2.0 to 9.2.1 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;3090](https://redirect.github.com/fluentassertions/fluentassertions/pull/3090)
- Bump actions/setup-dotnet from 4 to 5 by
[@&#8203;dependabot](https://redirect.github.com/dependabot)\[bot] in
[#&#8203;3092](https://redirect.github.com/fluentassertions/fluentassertions/pull/3092)
- Add lock file for nuget packages by
[@&#8203;jnyrup](https://redirect.github.com/jnyrup) in
[#&#8203;3084](https://redirect.github.com/fluentassertions/fluentassertions/pull/3084)
- Set `DisableImplicitNuGetFallbackFolder` by
[@&#8203;jnyrup](https://redirect.github.com/jnyrup) in
[#&#8203;3095](https://redirect.github.com/fluentassertions/fluentassertions/pull/3095)
- Bump Nugets by [@&#8203;jnyrup](https://redirect.github.com/jnyrup) in
[#&#8203;3096](https://redirect.github.com/fluentassertions/fluentassertions/pull/3096)
- Revert package locking by
[@&#8203;jnyrup](https://redirect.github.com/jnyrup) in
[#&#8203;3098](https://redirect.github.com/fluentassertions/fluentassertions/pull/3098)
- Clean-up tests related to exceptions by
[@&#8203;dennisdoomen](https://redirect.github.com/dennisdoomen) in
[#&#8203;3099](https://redirect.github.com/fluentassertions/fluentassertions/pull/3099)

**Full Changelog**:
<fluentassertions/fluentassertions@8.6.0...8.7.0>

</details>

---

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test/Directory.Build.props

@@ -9,7 +9,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="FluentAssertions" Version="8.6.0" />
+        <PackageReference Include="FluentAssertions" Version="8.7.0" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
         <PackageReference Include="xunit" Version="2.9.3" />
         <PackageReference Include="xunit.runner.visualstudio" Version="3.1.4">