Update `discovery.yml` with desired labels, description, kind, etc.
Due to Micaël's recent update for persisting settings in the system database, we know have more granular control over how the settings are consumed in the UI. We can now add labels, descriptions, kind (to map to the correct
input type), etc.
- update the https://gitlab.com/meltano/meltano/blob/master/src/meltano/core/bundle/discovery.yml with the preferred values