Feat: add new Markdown parser (#39800)

and change all the challenges to new `md` format.

curriculum/challenges/english/10-coding-interview-prep/rosetta-code/count-the-coins.md

@@ -1,20 +1,23 @@
 ---
-title: Count the coins
 id: 59713bd26bdeb8a594fb9413
+title: Count the coins
 challengeType: 5
 forumTopicId: 302238
 ---
 
-## Description
-<section id='description'>
-There are four types of common coins in <a href="https://en.wikipedia.org/wiki/United_States" target="_blank">US</a> currency:
+# --description--
+
+There are four types of common coins in [US](https://en.wikipedia.org/wiki/United_States) currency:
+
 <ul>
   <li>quarters (25 cents)</li>
   <li>dimes (10 cents)</li>
   <li>nickels (5 cents), and</li>
   <li>pennies (1 cent)</li>
 </ul>
+
 <p>There are six ways to make change for 15 cents:</p>
+
 <ul>
   <li>A dime and a nickel</li>
   <li>A dime and 5 pennies</li>
@@ -23,31 +26,28 @@ There are four types of common coins in <a href="https://en.wikipedia.org/wiki/U
   <li>A nickel and 10 pennies</li>
   <li>15 pennies</li>
 </ul>
-</section>
 
-## Instructions
-<section id='instructions'>
+# --instructions--
+
 Implement a function to determine how many ways there are to make change for a dollar using these common coins (1 dollar = 100 cents)
-</section>
 
-## Tests
-<section id='tests'>
+# --hints--
 
-```yml
-tests:
-  - text: <code>countCoins</code> should be a function.
-    testString: assert(typeof countCoins === 'function');
-  - text: <code>countCoins()</code> should return 242.
-    testString: assert.equal(countCoins(), 242);
+`countCoins` should be a function.
 
+```js
+assert(typeof countCoins === 'function');
 ```
 
-</section>
+`countCoins()` should return 242.
 
-## Challenge Seed
-<section id='challengeSeed'>
+```js
+assert.equal(countCoins(), 242);
+```
 
-<div id='js-seed'>
+# --seed--
+
+## --seed-contents--
 
 ```js
 function countCoins() {
@@ -56,15 +56,7 @@ function countCoins() {
 }
 ```
 
-</div>
-
-
-
-</section>
-
-## Solution
-<section id='solution'>
-
+# --solutions--
 
 ```js
 function countCoins() {
@@ -86,7 +78,4 @@ function countCoins() {
 
   return t[targetsLength - 1];
 }
-
 ```
-
-</section>