Merge branch 'custom-column-names' into localdb-tests

Author: Colin Young

src/Serilog.Sinks.MSSqlServer/Sinks/MSSqlServer/MSSqlServerSink.cs

@@ -389,12 +389,12 @@ private static bool TryChangeType(object obj, Type type, out object conversion)
         /// <param name="disposing"></param>
         protected override void Dispose(bool disposing)
         {
-            _token.Cancel();
-
             if (_eventsTable != null)
                 _eventsTable.Dispose();
 
             base.Dispose(disposing);
+
+            _token.Cancel();
         }
     }
 }