Add AWS section to make doc easier to expand

What does this MR do?

Following !32696 (merged), I realized that this doc will likely be expanded to add information for GCP and Azure in the future, per &1804. I tweaked it slightly to make it "ready" for other cloud provider details (when created), and we can now link to the AWS section directly for

#207830 (comment 350277923)

Related issues

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