Provider options in shared storage with `bucket` key even for Local

[vinicvaz]

When creating a workflow the provider_options key of the payload for shared storage is coming with bucket key even when running with local.
Bucket must be a key only when using shared_storage=s3.
For local the provider_options key must be an empty dictionary
Also base_folder must be treated as a provider option as well

[vinicvaz]

base_folder still out of provider_options, we must check why