Bump the testing group with 3 updates

Bumps the testing group with 3 updates: [FakeItEasy](https://github.com/FakeItEasy/FakeItEasy), [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) and [Verify.Xunit](https://github.com/VerifyTests/Verify).


Updates `FakeItEasy` from 8.0.0 to 8.1.0
- [Release notes](https://github.com/FakeItEasy/FakeItEasy/releases)
- [Commits](FakeItEasy/FakeItEasy@8.0.0...8.1.0)

Updates `Microsoft.NET.Test.Sdk` from 17.8.0 to 17.9.0
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Changelog](https://github.com/microsoft/vstest/blob/main/docs/releases.md)
- [Commits](microsoft/vstest@v17.8.0...v17.9.0)

Updates `Verify.Xunit` from 22.5.0 to 23.7.2
- [Release notes](https://github.com/VerifyTests/Verify/releases)
- [Commits](https://github.com/VerifyTests/Verify/commits/23.7.2)

---
updated-dependencies:
- dependency-name: FakeItEasy
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: testing
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: testing
- dependency-name: Verify.Xunit
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: testing
...

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

Author: dependabot[bot]

test/Tests.csproj

@@ -11,7 +11,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="FakeItEasy" Version="8.0.0" />
+    <PackageReference Include="FakeItEasy" Version="8.1.0" />
     <PackageReference Include="FakeItEasy.Analyzer.CSharp" Version="6.1.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
@@ -20,9 +20,9 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
     <PackageReference Include="Shouldly" Version="4.2.1" />
-    <PackageReference Include="Verify.Xunit" Version="22.5.0" />
+    <PackageReference Include="Verify.Xunit" Version="23.7.2" />
     <PackageReference Include="xunit" Version="2.6.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.5.4">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>