Removed default setting for EnableOptimisticDirectExecution

Author: akotalwar

Microsoft.Azure.Cosmos/src/RequestOptions/QueryRequestOptions.cs

@@ -49,7 +49,7 @@ public class QueryRequestOptions : RequestOptions
         /// <value>
         /// Direct (optimistic) execution offers improved performance for several kinds of queries such as a single partition streaming query.
         /// </value>
-        internal bool EnableOptimisticDirectExecution { get; set; } = false;
+        internal bool EnableOptimisticDirectExecution { get; set; }
 
         /// <summary>
         /// Gets or sets the maximum number of items that can be buffered client side during