Update src/ServiceControl.Contracts/MessageFailed.cs

Co-Authored-By: bording <bording@gmail.com>

Author: SeanFeldman

src/ServiceControl.Contracts/MessageFailed.cs

@@ -45,7 +45,7 @@ public class MessageFailed
         public FailureInfo FailureDetails { get; set; }
 
         /// <summary>
-        /// Details about the message itself
+        /// Details about the message itself.
         /// </summary>
         public Message MessageDetails { get; set; }
 
@@ -163,4 +163,4 @@ public class ExceptionInfo
 
         }
     }
-}
+}