Ember v5 - current ember-canary, ember-beta channels are failing under fastboot

`ember-data >= 4.12` causes breakage, 
It's due to what this PR attempts to fix: https://github.com/ember-fastboot/ember-cli-fastboot/pull/905

https://github.com/ember-fastboot/ember-cli-fastboot/issues/869
https://github.com/mainmatter/ember-cookies/issues/791