CLI for static assets

As of now, I (@gmaze) was creating and updating Argopy internal static asset files manually using a notebook.
I do this for each release.

But this should not be limited to my own making on my laptop and must be properly packaged on a dedicated CLI script located under the Argopy `./cli` folder.

Actions:
- Refactor my notebook as a clean CLI script.
- Commit the script on the `./cli` folder.
- Possibly include on a Github Action regular execution to update to the static files.

Start from the existing notebook used to create and update Argopy's internal static asset files, then trace how its steps can be packaged as a CLI script under ./cli. Done means the asset-generation workflow no longer depends on the reporter's laptop and the script is committed there; GitHub Actions execution is described only as a possible follow-up.

Written by the indexing model from the issue text.