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/arrayToCSV.md

@@ -2,8 +2,8 @@
 
 Converts a 2D array to a comma-separated values (CSV) string.
 
-Use `Array.map()` and `Array.join(delimiter)` to combine individual 1D arrays (rows) into strings.
-Use `Array.join('\n')` to combine all rows into a CSV string, separating each row with a newline.
+Use `Array.prototype.map()` and `Array.prototype.join(delimiter)` to combine individual 1D arrays (rows) into strings.
+Use `Array.prototype.join('\n')` to combine all rows into a CSV string, separating each row with a newline.
 Omit the second argument, `delimiter`, to use a default delimiter of `,`.
 
 ```js