feat!: remove provider check

[KyleTryon]

Changes

This removed the provider check step.

• The step aims to add CircleCI specific error messaging to help users configure the orb in theory but in practice may prevent the orb's usage.
• Each potential cloud provider may have many methods of authentication which are valid
• The AWS provider for instance at this time does not support role assumption
• Most other cloud providers are not implemented in the command
• The default error messages from the serverless cli should be clear enough to the issue

[brivu]

Looks good!

[orb-publisher]

Your development orb has been published. It will expire in 30 days.
You can preview what this will look like on the CircleCI Orb Registry at the following link:
https://circleci.com/developer/orbs/orb/circleci/serverless-framework?version=dev:aab4c35bdc4522df3a4477c6f709fbc1195c2cf1