fix(curriculum): Platformer Game specify argument for height property (freeCodeCamp#55826)

Co-authored-by: Tom <[email protected]>

Author: Supravisor

curriculum/challenges/english/15-javascript-algorithms-and-data-structures-22/learn-intermediate-oop-by-building-a-platformer-game/64c74e0064a9080443af0796.md

@@ -15,6 +15,13 @@ Remember to use the `this` keyword to access the properties.
 
 You should have a `height` property.
 
+```js
+const splitter = code.split("if (this.position.x < this.width) {")
+assert.match(splitter[1], /this\.height\s*=\s*proportionalSize\(\s*\d+\s*\)\s*;?/);
+```
+
+You should assign `proportionalSize(40)` to the `height` property.
+
 ```js
 const splitter = code.split("if (this.position.x < this.width) {")
 assert.match(splitter[1], /this\.height\s*=\s*proportionalSize\(\s*40\s*\)\s*;?/);