[8.1] Cherrypick revamped docs to current

[bmorelli25]

This PR cherrypicks some of Alex's changes introduced in #158 to current. The content in this PR is required for agent PRs to pass ci. Any additional changes to #158, including updates to monitoring-aws-lambda.asciidoc, will overwrite this PR when it is backported.

EDIT: Unfortunately, we can't just merge and backport #158, because the changes to monitoring-aws-lambda.asciidoc will break the doc build. #158 can only be merged and backported after the agent docs have been updated 🙃.

[ghost]

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• Start Time: 2022-03-29T19:32:48.217+0000

• Duration: 6 min 28 sec

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Total	84

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