Stop using deprecated get_secret_by_name & support secret path

[alexsegura]

This method/API endpoint is deprecated.

GetSecretByName usage is now deprecated.
Scaleway recommends that you use the ListSecrets request with the name filter.

I guess it would mean changing:

secret = api.get_secret_by_name(secret_name=name, region=region)

To:

secret = api.list_secrets(name=name, region=region)

Also, the scaleway_secret_version module should support the path argument, so that we can retrieve a secret with the same name, and a different path.