Change alert channel.

[Micheletto]

The current alert channel uses and AWS SNS to send to SMS. However, that has recently become complicated as we will need to register numbers to use after April 1st.

Here are some options to consider:

• Emit errors from the lambda function, and alert based on those errors.
• Use SNS to send Email to an alert notification address at Pagerduty.
• Keep current config, and register some numbers.

[hwine]

@Micheletto -- thanks for raising this! Can you answer the questions below, please?

1. I agree with you & bpitts that plumbing via pagerduty is the best solution.
2. I can't remember exactly what the current state is:
   • is there a diagram or description of what is currently enabled? (code link fine) I vaguely remember you having added a second SNS topic (for non-critical errors), but I may not have plumbed it into the lambda yet.
   • Also, I have a feeling that the current SMS is "in-addition-to" some email that exists. That may be "enough" (i.e. we could just disable SMS and be done).