Add error explanation in 1-percentage-change.js

Author: moses77-boop

Sprint-2/3-mandatory-interpret/1-percentage-change.js

@@ -28,4 +28,8 @@ console.log(`The percentage change is ${percentageChange}`);
 //    Line 4: Number()
 //    Line 5: priceAfterOneYear.replaceAll("," "")
 //    Line 5: Number()
-//    Line 9: console.log()
+//    Line 9: console.log()
+
+// b) Line 5 seems to broken.
+// Error message - SyntaxError: missing ) after argument list
+// Reason for error: There is a missing comma between two arguments of replaceAll.