Twemoji update to Unicode 15.1

[jgibbon]

We should update from 15.0.3 to 15.1

Previous Issue for 15.0.3: #561 Previous PR for 15.0.3: #563

Tasks:

• [x] Update svg files
• [x] Update Regex using https://github.com/jdecked/twemoji-parser/blob/main/src/lib/regex.js as a reference
• [x] Update https://github.com/jgibbon/fernie-emojidb (git submodule should be enough, since it already checked against 15.1) and use it to generate a new .db for emoji search