Provide endpoints showing which customers have access to which accounts.

Add new endpoints that list the customers linked to the view of an account.

List all customers for the (implicit) "owner" view.
obp/v2.2.0/my/banks/BANK_ID/accounts/ACCOUNT_ID/customer-views

List all customers for a certain view
obp/v2.2.0/banks/BANK_ID/accounts/ACCOUNT_ID/views/VIEW_ID/customer_views

List all Customers + Views they have access to:
obp/v2.2.0/banks/BANK_ID/accounts/ACCOUNT_ID/customer-views

Probably makes sense to have a customer-views resource like so:

customer-views:

[{
	"user": {
		"user_id": "5995d6a2-01b3-423c-a173-5481df49bdaf",
		"email": "robert.x.0.gh@example.com",
		"provider_id": "robert.x.0.gh",
		"provider": "OBP",
		"username": "robert.x.0.gh"
	},
	"customer": {
		"customer_id": "yauiuy67876f",
		"customer_number": "12345",
		"legal_name": "Robert Manchester"
	},
	"view": {
		"view_id": "owner",
		"short_name": "Accountant",
		"description": "For the accountants",
		"is_public": false
	}
}]

Get the customers like this:

Account -> View (e.g. owner) -> User -> User Customer Links -> Customer