feat(secrets): add Passbolt adapter

[acidtib]

Passbolt organizes secrets in folders (like coolfolder) and these folders can be nested (like coolfolder/prod, coolfolder/stg, etc). You can access secrets in these folders in two ways:

1. Using the --from option to specify the folder path --from coolfolder
2. Prefixing the secret names with the folder path coolfolder/REGISTRY_PASSWORD

The passbolt adapter does not use the --account option.

Site documentation PR: https://github.com/basecamp/kamal-site/pull/171