Avoid confusing prototype methods for static methods

Correct: `Array.from()` (it’s a static method)
Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method)

This patch uses the common `#` syntax to denote `.prototype.`.

snippets/arrayToHtmlList.md

@@ -2,7 +2,7 @@
 
 Converts the given array elements into `<li>` tags and appends them to the list of the given id.
 
-Use `Array.map()`, `document.querySelector()`, and an anonymous inner closure to create a list of html tags.
+Use `Array.prototype.map()`, `document.querySelector()`, and an anonymous inner closure to create a list of html tags.
 
 ```js
 const arrayToHtmlList = (arr, listID) =>