Update the ember-template-compiler to v4.1.0

[Windvis]

I started looking into #1018 again and I noticed the tests failed because the template compiler doesn't support the new helpers yet.

I just plucked this out of the ember-source package of a 4.1.0 Ember app. Let me know if there is a better way to update it 😄.

[Windvis]

The failing check seems unrelated to this change?

connect ECONNREFUSED 52.73.87.228:443

[ef4]

Yes, that CI failure is something in Github's caching layer as used by the Volta action and it seems to happen about 1% of the time, which means in our suite of 111 jobs it happens once almost every run. 🙃

[ef4]

Thanks for working on this.

This part of the test suite is lacking a way to test multiple ember versions. Can you verify (at least manually) that these changes to macro-maybe-attrs are compatible with the 3.25-era template-compiler that this PR is replacing?

Ultimately we need to finish moving all the node tests into the tests/scenarios so that they can be run under multiple ember versions.

[Windvis]

@ef4 The tests still pass with the template compiler of ember 3.25. I can split the loc commit in a separate branch and PR it on its own so that it can be verified through CI?

[ef4]

Thanks, nice work.