Extract authentication into the sdk

[Elod23]

Is your feature request related to a problem? Please describe.

To make the marketplace's work easier the whole authentication flow could be enforced directly from the sdk.

Describe the solution you'd like

User Story: As a marketplace, I want the SDK to enforce authentication whenever our customer calls a protected marketplace API endpoint, not when the SDK is instantiated.

Additional context

This would eliminate one marketplace burden and would enforce authentication only when it is strictly necessary.