[FEAT] Add/find logs for the coronalert-notify lambda

[acthelemann]

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Prerequisites

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Summary

Logs for the subscribe and unsubscribe lambdas can be found in CloudWatch, but not for the notify lambda. Maybe they're stored somewhere else or maybe they have to be "hooked up" to CloudWatch somehow.

• [ ] coronalert-notify logs can be read in the AWS console

Motivation

Debugging purposes.

Possible Alternatives

Use Twilio logs instead.