bitrot updates

[trentm]

The bitrot.js script should get some updates:

1. update to work again after updates to the .tav.yml format (using the recent version ranges mode)
2. add support for checking for newer Lambda runtimes (https://docs.aws.amazon.com/lambda/latest/dg/lambda-runtimes.html#runtimes-supported). See Lambda "nodejs20.x" is out, our published Lambda layers should say they support it #4033 where it currently takes a customer or someone noticing that we are out of date.
3. Run bitrot regularly (in GH actions?) so that we see the out-of-date state. Perhaps in GH actions with a slack notification.

[trentm]

For (2.) this might help:

% aws lambda publish-layer-version help | rg nodejs
            nodejs
            nodejs4.3
            nodejs6.10
            nodejs8.10
            nodejs10.x
            nodejs12.x
            nodejs14.x
            nodejs16.x
            nodejs4.3-edge
            nodejs18.x
            nodejs20.x

However, I'm not sure how to do a local install of latest aws for this and if it is worth it.

Q: How is release.yml getting the aws CLI tool?
A: It is in the GH-hosted runner ubuntu images by default: https://github.com/actions/runner-images/blob/main/images/ubuntu/Ubuntu2204-Readme.md#cli-tools