doesn't include blueprint changes to ember-cli-update.json

[kellyselden]

The latest ember-cli 3.26 includes a --embroider option in ember-cli-update.json. This does not come in when using ember-cli-update to do the update.

[rwjblue]

I wouldn't expect ember-cli-update when used for ember-cli@3.26.0 to add the flag to ember-cli-update.json. The default value in 3.26, was "classic" (aka non-Embroider) so the --embroider flag shouldn't be present.

However, when upgrading from 3.26 to 3.27 we definitely see the issue you are describing. Manual reproduction steps:

1. npx ember-cli@3.26.0 new test-ember-cli-update
2. npx ember-cli-update --package ember-cli --blueprint app --to 3.27.0-beta.1
3. Check config/ember-cli-update.json and ember-cli-build.js

The ember-cli-build.js includes Embroider "things" but the config/ember-cli-update.json does not include --embroider flag.

I created https://github.com/rwjblue/___test-ember-cli-update-for-embroider to show what I mean.