Removed explicit dependency on encoder package

Author: egil

src/Egil.RazorComponents.Testing.Library.csproj

@@ -26,8 +26,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Components" Version="$(AspNetCoreVersion)" />
     <PackageReference Include="Microsoft.AspNetCore.Components.Web" Version="$(AspNetCoreVersion)" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.2.0" />
-    <PackageReference Include="System.Text.Encodings.Web" Version="4.6.0-preview8.19405.3" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.2.0" />    
     <PackageReference Include="XMLUnit.Core" Version="2.7.1" />
     <PackageReference Include="xunit.assert" Version="2.4.1" />
     <PackageReference Include="xunit.extensibility.core" Version="2.4.1" />