What would help testing would be possibility to set `LEGAL_ENTITY_CHOICES` and `MARKETPLACE_PRODUCTS` in nise yaml file.

Currently it is used like this:
LEGAL_ENTITY_CHOICES = ("Red Hat", "Red Hat Inc.", "Amazon Web Services, Inc.")

MARKETPLACE_PRODUCTS = (
"Red Hat OpenShift Service on AWS",
"Red Hat Enterprise Linux 7",
"Red Hat Enterprise Linux 8",
)
 
we can set for example region but not these two (or maybe I just didn't find how to do it?) (edited) 
 
So the generator would look like this:

• MarketplaceGenerator:
  start_date: last_month
  product_sku: VEAJHRNAAAAA
  region: us-west-1a
  product_name: Red Hat Enterprise Linux 8
  legal_entity: Red Hat
  amount: 10
  rate: 2
  tags:\
  resourceTags/user:openshift_node: ocp-nod