Bump Microsoft.NET.Test.Sdk from 18.6.0 to 18.7.0 (#50)

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-version: 18.7.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Directory.Packages.props

@@ -11,7 +11,7 @@
   <ItemGroup>
     <PackageVersion Include="xunit" Version="$(XunitVersion)" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="$(XunitRunnerVersion)" />
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.6.0" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.7.0" />
     <PackageVersion Include="coverlet.collector" Version="10.0.0" />
   </ItemGroup>
   <!-- SourceLink -->