Upgrade Unicode database to v14.0.0 (#11308)

Closes #11288.

Author: eksperimental

lib/elixir/lib/string.ex

@@ -69,7 +69,7 @@ defmodule String do
   ## Code points and grapheme cluster
 
   The functions in this module act according to
-  [The Unicode Standard, Version 13.0.0](http://www.unicode.org/versions/Unicode13.0.0/).
+  [The Unicode Standard, Version 14.0.0](http://www.unicode.org/versions/Unicode14.0.0/).
 
   As per the standard, a code point is a single Unicode Character,
   which may be represented by one or more bytes.