fixed consumer method injection context bug. (#34)

src/DotNetCore.CAP/Internal/ConsumerInvokerFactory.cs

 using System;
 using DotNetCore.CAP.Abstractions;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 
 namespace DotNetCore.CAP.Internal
@@ -22,12 +23,15 @@ namespace DotNetCore.CAP.Internal
 
         public IConsumerInvoker CreateInvoker(ConsumerContext consumerContext)
         {
-            var context = new ConsumerInvokerContext(consumerContext)
+            using(var scope = _serviceProvider.CreateScope())
             {
-                Result = new DefaultConsumerInvoker(_logger, _serviceProvider, _modelBinderFactory, consumerContext)
-            };
+                var context = new ConsumerInvokerContext(consumerContext)
+                {
+                    Result = new DefaultConsumerInvoker(_logger, scope.ServiceProvider, _modelBinderFactory, consumerContext)
+                };
 
-            return context.Result;
+                return context.Result;
+            }
         }
     }
 }
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