Fix Processor IgnoreFailure property name mapping (#4114)

(cherry picked from commit 66d9b48)

Author: blemasle

src/Nest/Ingest/Processor.cs

@@ -34,7 +34,7 @@ public interface IProcessor
 		string Tag { get; set; }
 
 		/// <summary> When a failure happens, ignore it and proceed to the next processor </summary>
-		[DataMember(Name = "ignore_failue")]
+		[DataMember(Name = "ignore_failure")]
 		bool? IgnoreFailure { get; set; }
 	}