Bump Microsoft.NET.Test.Sdk from 17.14.1 to 18.0.0

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-version: 18.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

tests/Directory.Build.props

@@ -6,7 +6,7 @@
     <NoWarn>$(NoWarn);CS1591;NU1701</NoWarn>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
     <PackageReference Include="xunit" Version="2.9.3" />
     <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5" />
     <PackageReference Include="GitHubActionsTestLogger" Version="2.4.1" PrivateAssets="All" />