INF-506 fix prod redirect url

[cat5inthecradle]

Prod is special, but the redirect lambda assumed prod was just like staging and test, which meant that it is set up to redirect to autoscale-prod.code.org instead of the special prod additional URL code.org. Similar to how we needed to conditionally specify a Subject Alternative Name for the certificate in prod, we need to have prod redirect to this URL instead.

Links

Jira Tickets

• https://codedotorg.atlassian.net/jira/software/c/projects/INF/boards/57?modal=detail&selectedIssue=INF-543
• https://codedotorg.atlassian.net/jira/software/c/projects/INF/boards/57?modal=detail&selectedIssue=INF-506

Follow-up work

Continue INF-506 and INF-543

PR Checklist:

• Tests provide adequate coverage
• Privacy and Security impacts have been assessed
• Code is well-commented
• New features are translatable or updates will not break translations
• Relevant documentation has been added or updated
• User impact is well-understood and desirable
• Pull Request is labeled appropriately
• Follow-up work items (including potential tech debt) are tracked and linked

[Hamms]

couple minor syntax/code organization nits, but overall LGTM!

[cat5inthecradle]

Following up after the staging deploy. This PR caused no actual changes to the cloudformation template, so that means my understanding of the variables/functions was correct.