BREAKING(aws): Deprecate trivy aws as subcmd in favour of a plugin

[simar7]

Description

Deprecates the aws from Trivy. Users can now install the aws plugin instead.

More details can be found in the deprecation notice here

Related PRs

• (needs to be merged first) feat(plugin): trivy-aws as a plugin for Trivy trivy-aws#153
• feat(plugin): Add trivy-aws as a plugin trivy-plugin-index#8
• chore(plugin): Rename plugin trivy-aws#181
• chore(plugin): Rename trivy-aws plugin trivy-plugin-index#12

Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

[simar7]

@knqyf263 once you're back, could you also take a look?

[knqyf263]

We need some changes after aquasecurity/trivy-aws#181 and aquasecurity/trivy-plugin-index#12, but we can merge this PR and open another PR.