Update version auth at edge to use node v20

[noah-paige]

Feature or Bugfix

• Enhancement

Detail

• Update serverless application Auth At Edge to use node v20

Relates

• Upgrade lambdas using v16 Node.js runtime #939

Security

Please answer the questions below briefly where applicable, or write N/A. Based on
OWASP 10.

• Does this PR introduce or modify any input fields or queries - this includes
  fetching data from storage outside the application (e.g. a database, an S3 bucket)?
  • Is the input sanitized?
  • What precautions are you taking before deserializing the data you consume?
  • Is injection prevented by parametrizing queries?
  • Have you ensured no eval or similar functions are used?
• Does this PR introduce any functionality or component that requires authorization?
  • How have you ensured it respects the existing AuthN/AuthZ mechanisms?
  • Are you logging failed auth attempts?
• Are you using or adding any cryptographic features?
  • Do you use a standard proven implementations?
  • Are the used keys controlled by the customer? Where are they stored?
• Are you introducing any new policies/roles/users?
  • Have you used the least-privilege principle? How?

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[noah-paige]

Tested in AWS to ensure:

• Clean Upgrade via CodePipeline
• Node version for AuthAtEdge Lambda Functions updated to v20
• UserGuide still accessible with required user login creds

[petrkalos]

in case you haven't already can you also test the following scenarios

• fresh login from an incognito tab
• logout and login again

[noah-paige]

in case you haven't already can you also test the following scenarios

* fresh login from an incognito tab

* logout and login again

Tested and all working as expected