Clean up the old versions of the redirect Lambdas

[alexwlchan]

We've had an email from AWS:

We are contacting you as we have identified that your AWS Account currently has one or more Lambda functions using Node.js 12 runtime.

We are ending support for Node.js 12 in AWS Lambda. This follows Node.js 12 End-Of-Life (EOL) reached on April 30, 2022.

If you run the command they specify, you discover that all the affected Lambda functions are old versions of the redirect Lambda from this repository:

Counter({'arn:aws:lambda:us-east-1:760097843905:function:cf_edge_wellcome_library_redirect': 93,
         'arn:aws:lambda:us-east-1:760097843905:function:cf_edge_wellcome_library_passthru': 74,
         'arn:aws:lambda:us-east-1:760097843905:function:cf_edge_wellcome_library_blog_redirect': 58,
         'arn:aws:lambda:us-east-1:760097843905:function:cf_edge_wellcome_library_archive_redirect': 41,
         'arn:aws:lambda:us-east-1:760097843905:function:cf_edge_wellcome_library_encore_redirect': 38,
         'arn:aws:lambda:us-east-1:760097843905:function:cf_edge_dlcs_path_rewrite': 24})

We're using Node 16 for all the current versions (see bce1d1b), so nothing is going to break when Node.js 12 goes EOL – but we don't need these old versions, so we should clean them up so we don't get any more warnings from AWS.

[alexwlchan]

I forgot to write down the command, which is:

aws lambda list-functions --function-version ALL $ env AWS_PROFILE=platform-dev aws lambda list-functions --function-version ALL --region us-east-1 --output text --query "Functions[?Runtime=='nodejs12.x'].FunctionArn"

[alexwlchan]

Okay, so it turns out to be a bit more complicated – the cf_edge_dlcs_path_write Lambda is still running a Nodejs 12.x runtime, so we can't delete it. That lives in a separate repo, so I'll open a ticket for that.