chore(cli): check if returnValue is undefined (#18943)

Need to check if returnValue is undefined not if it is defined.


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Author: corymhall

packages/aws-cdk/bin/cdk.ts

@@ -309,7 +309,7 @@ async function initCommandLine() {
         break;
     }
 
-    if (returnValue !== undefined) {
+    if (returnValue === undefined) {
       returnValue = await main(cmd, argv);
     }