changed the final test.

Author: SaiedaJN

src/functions.ts

@@ -47,13 +47,10 @@ export function isQuestion(message: string): boolean {
 * upper or lower case), then return `false`. Otherwise, return `null`.
 */
 export function convertYesNo(word: string): boolean | null {
-   if (word === "yes" || word === "YES") {
-       return true;
-   } else if (word == "no" || word === "NO") {
-       return false;
-   } else {
-       return null;
-   }
+   return(
+    word.toUpperCase()== "YES" ? true: word.toUpperCase() == "NO"? false: null
+    );
+
 }