Implement next version of the provider interface

[1ucian0]

All qiskit providers (aer, ibmq, aqt, basicaer) moved to new versioned provider interface for Qiskit 0.25.0 (qiskit.providers.BackendV1, qiskit.providers.JobV1, etc)

This issue is to track development the next version of the abstract class definitions for the objects in the provider interface. Primarily:

• BackendV2 which moves us towards a native terra object model for all interaction with providers (see: Add BackendV2 abstract class #5885 )
• JobV2 which simplifies the structure and integrates results natively without needing a separate Result container object
• ProvidersV2 which improves the interface for discovering available backends and brings in an attribute (primarily for tab completion) (see: Add ProviderV2 a second version of Provider abstract class #5629 )