Add Microsoft.AspNetCore.Mvc.Core package reference

Author: alex-kulakov

Extensions/Xtensive.Orm.Web/Xtensive.Orm.Web.csproj

@@ -17,6 +17,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Http.Abstractions" Version="2.2.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Abstractions" Version="2.2.0" />
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.Core" Version="2.2.0" />
     <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="3.1.0" />
     <PackageReference Include="System.Configuration.ConfigurationManager" Version="4.7.0" />
   </ItemGroup>