feat: [SKU modularization] sku handler interface

[smritidahal653]

Reason for Change:
Adding a CloudSKUHandler interface that will be used to modularize gpu skus across multiple cloud platforms

Requirements

• added unit tests and e2e tests (if applicable).

Issue Fixed:

Notes for Reviewers:
The cloud specific implementations and fixes/updates to current code will be part of future PRs.

[ishaansehgal99]

Now that we are extending this functionality, I would suggest we place this and sku_config.go in pkg/resources folder. or introducing a new folder like pkg/cloud or pkg/nodes

[Fei-Guo]

Now that we are extending this functionality, I would suggest we place this and sku_config.go in pkg/resources folder. or introducing a new folder like pkg/cloud or pkg/nodes

Yes. or just pkg/sku.

[smritidahal653]

Now that we are extending this functionality, I would suggest we place this and sku_config.go in pkg/resources folder. or introducing a new folder like pkg/cloud or pkg/nodes

I am going to move cloud_sku_handler.go to pkg/sku. However, I am going to leave sku_config as is right now since the file will be eventually deleted. I will move all implementations of CloudSKUHandler to the same package though.