(feat) SREIN-32 Drop [www.]firefox.com redirects to mozorg, etc

[stevejalim]

This can be merged as a cleanup task after we've pointed www.firefox.com at Springfield.

The redirects here that need to be persisted (which are basically all of them apart from the unfck and universityambassadors ones, IIRC) will be added to Springfield before it starts serving www.firefox.com

Refractr PR Checklist

JIRA ticket: [link to relevant JIRA or other system ticket]

When creating a PR for Refractr, confirm you've done the following steps for a smooth CI and CD experience:

• Have you updated the relevant YAML in the PR?
• Have you checked the relevant YAML for any possible dupes regarding your domain?
• Have you checked if there are any TLS cert concerns - e.g. if the domain being redirected already exists, and it is being changed to point at refractr, is a temporary TLS 'outage' while waiting for certification via HTTP challenge okay? If not, add a note to the JIRA ticket.
• If desired, have you generated the nginx config manually to confirm updates work as expected?

After PR merge, next steps include:

• A merge to the main branch will automatically deploy refractr's stage environment -- deploying the prod environment requires a GitHub release to be created.
• Once deployed, refractr's certmap must be updated and DNS entries must be changed -- SRE can help with this. Please pull someone in on the JIRA ticket or ask for help in #sre on Slack.

[stevejalim]

Question: do we need to keep something that routes the apex firefox.com domain to www.firefox.com ?

[izo3]

Updated.

[stevejalim]

@izo3 @ahoneiser May I leave this PR to you to take over and merge at the right time?