ci: auto-update script detection and workflow release

[GreatWizard]

Let's automate all the boring stuff :) The package is fairly simple to be automated from unicode.org new release detection to publish on npm.

I create a new script (gen.sh) in order to detect the new releases automatically from unicode.org and update the package.json version and emoji JSON files.

Then, I add 2 GitHub actions workflows:

• update-emoji.yml: scheduled every night, it runs the build process and make a Pull Request (auto mergeable)
• tag-release-publish.yml: detect the package.json version change and create a tag on Github, then create the release page and push the new package on NPM

In order to works, we need to set up 3 secrets:

• npm_automation_token: token to auto-publish on NPM
• github_write_token: GitHub token with write access on the repo
• github_repo_token: GitHub token with repo access on the repo

[amio]

Great idea! Sorry for missing PRs for a long time, would you mind continue work on this? @GreatWizard We can use this to release the update for v15.0