AWS iot medium security documentation change
Summary
Renamed and restructured documentation about HTTP action destinations. Added Certificate Authority support details, clarified destination states (ENABLED/DISABLED/IN_PROGRESS/ERROR), and enhanced endpoint security requirements.
Security assessment
Added explicit note that self-signed certificates are not supported, and specified AWS Private CA/Let's Encrypt as required authorities. This enforces secure HTTPS communication by preventing use of untrusted certificates, addressing potential man-in-the-middle risks.