fix: use optional chaining to avoid errors (#57759)

curriculum/challenges/english/15-javascript-algorithms-and-data-structures-22/build-a-cash-register-project/build-a-cash-register.md

@@ -111,7 +111,7 @@ cashInput.dispatchEvent(new Event('change'));
 purchaseBtn.click();
 assert.strictEqual(
   alertMessage
-    .trim()
+    ?.trim()
     .replace(/[.,?!]+$/g, '')
     .toLowerCase(),
   'customer does not have enough money to purchase the item'
@@ -148,7 +148,7 @@ cashInput.dispatchEvent(new Event('change'));
 purchaseBtn.click();
 assert.strictEqual(
   alertMessage
-    .trim()
+    ?.trim()
     .replace(/[.,?!]+$/g, '')
     .toLowerCase(),
   'customer does not have enough money to purchase the item'

curriculum/challenges/english/15-javascript-algorithms-and-data-structures-22/build-a-palindrome-checker-project/build-a-palindrome-checker.md

@@ -70,7 +70,7 @@ window.alert = (message) => alertMessage = message; // Override alert and store
 inputEl.value = '';
 inputEl.dispatchEvent(new Event('change'))
 checkBtn.click();
-assert.strictEqual(alertMessage.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please input a value');
+assert.strictEqual(alertMessage?.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please input a value');
 ```
 
 When the `#text-input` element only contains the letter `A` and the `#check-btn` element is clicked, the `#result` element should contain the text `"A is a palindrome"`.

curriculum/challenges/english/15-javascript-algorithms-and-data-structures-22/build-a-pokemon-search-app-project/build-a-pokemon-search-app.md

@@ -153,7 +153,7 @@ async () => {
     if (!res.ok) {
       await new Promise(resolve => setTimeout(resolve, 1000)); // Additional delay to allow the alert to trigger
 
-      assert.include(['pokémon not found', 'pokemon not found'], alertMessage.trim().replace(/[.,?!]+$/g, '').toLowerCase());
+      assert.include(['pokémon not found', 'pokemon not found'], alertMessage?.trim().replace(/[.,?!]+$/g, '').toLowerCase());
     }
   } catch (err) {
     throw new Error(err);
@@ -375,7 +375,7 @@ async () => {
     if (!res.ok) {
       await new Promise(resolve => setTimeout(resolve, 2000)); // Additional delay to allow the alert to trigger
 
-      assert.include(['pokémon not found', 'pokemon not found'], alertMessage.trim().replace(/[.,?!]+$/g, '').toLowerCase());
+      assert.include(['pokémon not found', 'pokemon not found'], alertMessage?.trim().replace(/[.,?!]+$/g, '').toLowerCase());
     }
   } catch (err) {
     throw new Error(err);

curriculum/challenges/english/15-javascript-algorithms-and-data-structures-22/build-a-telephone-number-validator-project/build-a-telephone-number-validator.md

@@ -103,7 +103,7 @@ window.alert = (message) => alertMessage = message; // Override alert and store
 
 userInput.value = '';
 checkBtn.click();
-assert.strictEqual(alertMessage.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please provide a phone number');
+assert.strictEqual(alertMessage?.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please provide a phone number');
 ```
 
 When you click on the `#clear-btn` element, the content within the `#results-div` element should be removed.

curriculum/challenges/english/15-javascript-algorithms-and-data-structures-22/learn-recursion-by-building-a-decimal-to-binary-converter/64475c0b61cddb6feaab4e2e.md

@@ -31,7 +31,7 @@ window.alert = (message) => alertMessage = message; // Override alert and store
 numberInput.value = '';
 checkUserInput();
 
-assert.strictEqual(alertMessage.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please provide a decimal number greater than or equal to 0');
+assert.strictEqual(alertMessage?.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please provide a decimal number greater than or equal to 0');
 ```
 
 # --seed--

curriculum/challenges/english/25-front-end-development/lab-palindrome-checker/657bdc55a322aae1eac3838f.md

@@ -68,7 +68,7 @@ window.alert = (message) => alertMessage = message; // Override alert and store
 inputEl.value = '';
 inputEl.dispatchEvent(new Event('change'))
 checkBtn.click();
-assert.strictEqual(alertMessage.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please input a value');
+assert.strictEqual(alertMessage?.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please input a value');
 ```
 
 When the `#text-input` element only contains the letter `A` and the `#check-btn` element is clicked, the `#result` element should contain the text `"A is a palindrome"`.

curriculum/challenges/english/25-front-end-development/workshop-decimal-to-binary-converter/64475c0b61cddb6feaab4e2e.md

@@ -31,7 +31,7 @@ window.alert = (message) => alertMessage = message; // Override alert and store
 numberInput.value = '';
 checkUserInput();
 
-assert.strictEqual(alertMessage.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please provide a decimal number greater than or equal to 0');
+assert.strictEqual(alertMessage?.trim().replace(/[.,?!]+$/g, '').toLowerCase(), 'please provide a decimal number greater than or equal to 0');
 ```
 
 # --seed--