Release v4.0.0

Gotta go fast 🧗

git-cliff-action is now waaaaaaaay faster.

We switched to a classic bash script to download the git-cliff binary instead of a Docker action.
So, no more building images, it just downloads and runs. Vroooom! 💨

Thanks @M0NsTeRRR for the implementation in #26

Version input ✨

Also, you can now specify a git-cliff version to run:

- name: Generate a changelog
  uses: orhun/git-cliff-action@v4
  with:
    version: latest
    config: cliff.toml
    args: --verbose

The default is v2.5.0 as of now, but you can also use latest.