deps(test): update vstest monorepo (#1159)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| [Microsoft.NET.Test.Sdk](https://redirect.github.com/microsoft/vstest)
| `18.6.0` → `18.7.0` |
![age](https://developer.mend.io/api/mc/badges/age/nuget/Microsoft.NET.Test.Sdk/18.7.0?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/nuget/Microsoft.NET.Test.Sdk/18.6.0/18.7.0?slim=true)
|

---

### Release Notes

<details>
<summary>microsoft/vstest (Microsoft.NET.Test.Sdk)</summary>

###
[`v18.7.0`](https://redirect.github.com/microsoft/vstest/releases/tag/v18.7.0)

#### What's Changed

- Add ARM64 msdia140.dll support to test platform packages by
[@&#8203;jamesmcroft](https://redirect.github.com/jamesmcroft) in
[#&#8203;15689](https://redirect.github.com/microsoft/vstest/pull/15689)
- Update System.Memory from 4.5.5 to 4.6.3 by
[@&#8203;nohwnd](https://redirect.github.com/nohwnd) in
[#&#8203;15706](https://redirect.github.com/microsoft/vstest/pull/15706)

#### New Contributors

- [@&#8203;jamesmcroft](https://redirect.github.com/jamesmcroft) made
their first contribution in
[#&#8203;15689](https://redirect.github.com/microsoft/vstest/pull/15689)

**Full Changelog**:
<microsoft/vstest@v18.6.0...v18.7.0>

</details>

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test/Directory.Build.props

@@ -10,7 +10,7 @@
 
     <ItemGroup>
         <PackageReference Include="FluentAssertions" Version="8.10.0" />
-        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.6.0" />
+        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.7.0" />
         <PackageReference Include="xunit.v3" Version="3.2.2" />
         <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>