Replace collections on `europe` front if participating in the Europe beta test

What is the value of this and can you measure success?

Setting up phase 2 of the Europe beta experiment test plan to show the containers on the Europe beta front instead of those on the Europe front for users participating in the test

If a user requests the europe front and is not particpating in the test, the europe collections are returned as usual.

If a user requests any other front and is either participating or not participating in the Europe beta test, the collections configured for that front are unchanged.

Trello ticket link

What does this change?

Adjusts the logic in renderFrontPressResult for fetching the futureFaciaPage to swap the collections returned in the response if a user is participating in the Europe beta test and they are requesting the Europe front.

All other fields remain the same apart from collections which returns those on the hidden europe-beta front instead of the usual collections returned from the europe front.

Screenshots

Checklist

[ ] Tested locally, and on CODE if necessary
[ ] Will not break dotcom-rendering
[ ] Will not break our database – if updating CAPI, updated and committed the database files
[ ] Meets our accessibility standards
- [ ] Tested with screen reader
- [ ] Navigable with keyboard
- [ ] Colour contrast passed

guardian / frontend