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/differenceWith.md

@@ -2,7 +2,7 @@
 
 Filters out all values from an array for which the comparator function does not return `true`.
 
-Use `Array.filter()` and `Array.findIndex()` to find the appropriate values.
+Use `Array.prototype.filter()` and `Array.prototype.findIndex()` to find the appropriate values.
 
 ```js
 const differenceWith = (arr, val, comp) => arr.filter(a => val.findIndex(b => comp(a, b)) === -1);