Normalize codepoints for Twemoji

[tobyzerner]

This PR piggybacks on #6. cc/ @JoshyPHP

I noticed some random emojis weren't being converted, even with #6. Things like 🏝, ❤️‍🔥, and 🏃🏻‍♀️.

Now I'll be honest, I have no idea how Unicode works.

But I know that @JoshyPHP does, so I tried adapting this logic from the s9e/TextFormatter Emoji plugin, to normalize the codepoints so they work with Twemoji:

// Twemoji sequence, leading zeroes are removed and VS-16 are removed from non-ZWJ sequences
$tseq = ltrim($hex, '0');
if (strpos($tseq, '-200d') === false)
{
    $tseq = str_replace('-fe0f', '', $tseq);
}

And lo and behold, it works! I added some tests with some of the more complex emojis that were failing before, which work great now.

[Gummibeer]

Hey, thanks for your contribution and sorry for the massive delay! 🙏
It's released now. 🎉🚀
https://github.com/Astrotomic/php-twemoji/releases/tag/0.2.2

In case you want to check why it took so long:
https://gummibeer.dev/blog/2022/end-of-an-era/

[tobyzerner]

Hey @Gummibeer, thanks for sharing your story. I can definitely relate! Glad you're on a better path now. Wishing you all the best. Thank you for the merge + release!