Optimize get with attributes

commit_hash:aa16f9a56a3369683a1cca1879cd2834e6f13ca2

Author: babenko

yt/yt/core/ytree/attribute_filter.cpp

@@ -368,7 +368,7 @@ std::unique_ptr<TAttributeFilter::IFilteringConsumer> TAttributeFilter::CreateFi
             { }
 
         private:
-            IYsonConsumer* TargetConsumer_;
+            IYsonConsumer* const TargetConsumer_;
         };
 
         return std::make_unique<TBypassFilteringConsumer>(targetConsumer);