Added solution to remove-whitespace-from-start-and-end.english.md (#35145)

* Update remove-whitespace-from-start-and-end.english.md

* includes whole solution now

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/regular-expressions/remove-whitespace-from-start-and-end.english.md

@@ -52,6 +52,8 @@ let result = hello; // Change this line
 <section id='solution'>
 
 ```js
-// solution required
+let hello = "   Hello, World!  ";
+let wsRegex = /^(\s+)(.+[^\s])(\s+)$/;
+let result = hello.replace(wsRegex, '$2');
 ```
 </section>