fix(curriculum): add test for href attribute in cat photo app (#60176)

Co-authored-by: Ilenia <26656284+ilenia-magoni@users.noreply.github.com>

curriculum/challenges/english/14-responsive-web-design-22/learn-html-by-building-a-cat-photo-app/5dfa30b9eacea3f48c6300ad.md

@@ -70,6 +70,21 @@ assert(
 );
 ```
 
+Your anchor (`a`) element does not have an `href` attribute. Check that there is a space after the opening tag's name and/or there are spaces before all attribute names.
+
+```js
+assert.isTrue(document.querySelectorAll('a')[2]?.hasAttribute('href'));
+```
+
+Your anchor (`a`) element should link to `https://freecatphotoapp.com`. You have either omitted the URL or have a typo.
+
+```js
+assert.equal(
+  document.querySelectorAll('a')[2]?.getAttribute('href').trim(),
+    'https://freecatphotoapp.com'
+);
+```
+
 Your `img` element should be nested within the anchor (`a`) element. The entire `img` element should be inside the opening and closing tags of the anchor (`a`) element.
 
 ```js