Deployment on AWS lambda

[hmacdope]

We need to run a trial deployment on AWS lambda, likely following guide from https://github.com/slackapi/bolt-python/blob/main/examples/aws_lambda/aws_lambda.py, but potentially using an image based deployment.

[hmacdope]

Will tap @mikemhenry here for assistance, as we may need OE secret inside lambda, unsure if we want to bake into an image, instead we may be able to use a setup like this : https://aws.amazon.com/blogs/compute/sharing-secrets-with-aws-lambda-using-aws-systems-manager-parameter-store/

[hmacdope]

On hold for now in favour of #8