Bump Microsoft.NET.Test.Sdk from 18.8.1 to 18.9.0 (#3054)

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-version: 18.9.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-version: 18.9.0
  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]

test/Microsoft.OpenApi.Hidi.Tests/Microsoft.OpenApi.Hidi.Tests.csproj

@@ -14,7 +14,7 @@
 
   <ItemGroup>
     <PackageReference Include="coverlet.msbuild" Version="10.0.1" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.8.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
     <PackageReference Include="Moq" Version="4.20.72" />
     <PackageReference Include="xunit.v3" Version="3.2.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5" PrivateAssets="all" />

test/Microsoft.OpenApi.Readers.Tests/Microsoft.OpenApi.Readers.Tests.csproj

@@ -17,7 +17,7 @@
     <ItemGroup>
         <PackageReference Include="coverlet.collector" Version="10.0.1" PrivateAssets="all" />
         <PackageReference Include="coverlet.msbuild" Version="10.0.1" PrivateAssets="all" />
-        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.8.1" />
+        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
         <PackageReference Include="FluentAssertions" Version="7.2.2" />
         <PackageReference Include="xunit.v3" Version="3.2.2" />
         <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5" PrivateAssets="all" />

test/Microsoft.OpenApi.Tests/Microsoft.OpenApi.Tests.csproj

@@ -11,7 +11,7 @@
     <PackageReference Include="coverlet.collector" Version="10.0.1" PrivateAssets="all" />
     <PackageReference Include="coverlet.msbuild" Version="10.0.1" PrivateAssets="all" />
     <PackageReference Include="FluentAssertions" Version="7.2.2" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.8.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
     <PackageReference Include="Moq" Version="4.20.72" />
     <PackageReference Include="Verify.XunitV3" Version="31.28.0" />
     <PackageReference Include="xunit.v3" Version="3.2.2" />