fix(curriculum): replace quote marks with back ticks for text (freeCodeCamp#58517)

Author: Supravisor

curriculum/challenges/english/14-responsive-web-design-22/learn-html-by-building-a-cat-photo-app/5dc1798ff86c76b9248c6eb3.md

@@ -46,7 +46,7 @@ assert(
 );
 ```
 
-Your `h1` element's text should be 'CatPhotoApp'. You have either omitted the text or have a typo.
+Your `h1` element's text should be `CatPhotoApp`. You have either omitted the text or have a typo.
 
 ```js
 assert(document.querySelector('h1').innerText.toLowerCase() === 'catphotoapp');
@@ -64,7 +64,7 @@ Your `h2` element should have a closing tag. Closing tags have a `/` just after
 assert(code.match(/<\/h2\>/));
 ```
 
-Your `h2` element's text should be 'Cat Photos'. Only place the text `Cat Photos` between the opening and closing `h2` tags.
+Your `h2` element's text should be `Cat Photos`. Only place the text `Cat Photos` between the opening and closing `h2` tags.
 
 ```js
 assert(document.querySelector('h2').innerText.toLowerCase() === 'cat photos');