Drift Detection support

Have you guys thought of having a built-in support for drift detection? That would have been handy if when calling status amplify will warn the user that the stack has drifted. Just thinking, this feature is pretty clear and does feel like complex implementation-wise, would you be open for a pull request for this?

Start by locating the Amplify CLI status command and how it currently reports stack state. Review the available AWS stack drift information and define the warning behavior, including what status output should show when drift is detected.

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