Emoji: Update the Twemoji library to version 17.0.3.

Some Emoji characters have a default text presentation defined in the Unicode specification. However, some of these characters (mainly ↗ ↘ ↙ ↖) are incorrectly being converted to an emoji character instead due to a bug in the Twemoji library.

Version `17.0.3` fixes this bug and ↗ ↘ ↙ ↖ characters are now presented as intended.

A full list of changes in this release can be found on GitHub: jdecked/twemoji@v17.0.2...v17.0.3.

Because there are no visual modifications to the image assets, a new folder has not been pushed to the WordPress.org CDN and core will continue to reference `/images/core/emoji/17.0.2` to avoid needlessly busting caches.

Props jdecked, joen, westonruter, peterwilsoncc, jorbin, siliconforks, desrosj, presskopp, wildworks, audrasjb, iflairwebtechnologies.
Fixes #64318.

git-svn-id: https://develop.svn.wordpress.org/trunk@62457 602fd350-edb4-49c9-b593-d223f7449a82

Author: desrosj