Fix invalid comment example in Snippet24 by replacing it with a valid expression statement (#46378)

* Fixed bug 46309.

* Initialize x.

---------

Co-authored-by: Adit Sheth <[email protected]>

Author: shethaadit

samples/snippets/csharp/VS_Snippets_VBCSharp/csProgGuideStatements/CS/Statements.cs

@@ -535,8 +535,9 @@ void TestMethod(string s)
                 // Expression statement (assignment).
                 area = 3.14 * (radius * radius);
 
-                // Error. Not  statement because no assignment:
-                //circ * 2;
+                // Expression statement (result discarded).
+                int x = 0;
+                x++;
 
                 // Expression statement (method invocation).
                 System.Console.WriteLine();