refactor(Core.Abstractions): update to support net 4.6.2

DigitalData.Core.Abstractions/DeferredServiceProvider.cs

@@ -1,4 +1,5 @@
-namespace DigitalData.Core.Abstractions;
+#if NET
+namespace DigitalData.Core.Abstractions;
 
 /// <summary>
 /// A deferred implementation of <see cref="IServiceProvider"/> that allows the <see cref="IServiceProvider"/> instance 
@@ -38,3 +39,4 @@ public class DeferredServiceProvider : IServiceProvider
         return _serviceProvider.Value.GetService(serviceType);
     }
 }
+#endif