Fix incorrect XML Comment

Author: sander1095

src/Mvc/Mvc.Core/src/ProducesDefaultResponseTypeAttribute.cs

@@ -40,7 +40,7 @@ public ProducesDefaultResponseTypeAttribute(Type type)
     public int StatusCode { get; }
 
     /// <summary>
-    /// Gets the description of the response.
+    /// Gets or sets the description of the response.
     /// </summary>
     public string? Description { get; set; }