I forked the plugin, added Gutenberg support

I created a fork. Refactored, fixed bugs. Added Gutenberg support. See:
https://www.ads-software.com/plugins/urvanov-syntax-highlighter/
You can give me bug fixing pull request here:
https://github.com/urvanov-ru/crayon-syntax-highlighter
I extremely use my forked version in my personal blog https://urvanov.ru, so. I think, I will support the forked version for a long time.