Improve deprecations

[cibernox]

@iezer I'm working on improving the deprecations.

[iezer]

@cibernox Awesome, thanks for picking this up. I wonder if it's possible to detect if a user is using the old syntax of moduleFor and passing beforeEach and afterEach, versus the new syntax of calling module and setupRenderingTest.

[cibernox]

@iezer That is what I'm doing here: https://github.com/cibernox/ember-native-dom-helpers/pull/145/files#diff-36ccf1b6880df69c7336caa0370773df

I'll try to find time to finish it tomorrow or on saturday.

[iezer]

👍 That looks great. I misread that as merely checking for @ember/test-helpers but now I see you're checking !!getContext()