Merge pull request #1374 from SteamRE/dependabot/nuget/SteamKit2/xunit-2.9.0

Bump xunit from 2.8.1 to 2.9.0 in /SteamKit2

Author: yaakov-h

SteamKit2/Tests/Tests.csproj

@@ -11,7 +11,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNet.WebApi.Client" Version="6.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-    <PackageReference Include="xunit" Version="2.8.1" />
+    <PackageReference Include="xunit" Version="2.9.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>