Merge pull request #1048 from microsoft/dependabot/nuget/Verify.Xunit-18.0.0

Bump Verify.Xunit from 17.10.2 to 18.0.0

Author: baywet

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

@@ -20,7 +20,7 @@
     <PackageReference Include="Moq" Version="4.18.2" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
     <PackageReference Include="SharpYaml" Version="2.1.0" />
-    <PackageReference Include="Verify.Xunit" Version="17.10.2" />
+    <PackageReference Include="Verify.Xunit" Version="18.0.0" />
     <PackageReference Include="xunit" Version="2.4.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">
       <PrivateAssets>all</PrivateAssets>