@ember/jquery detection seems off

[rwjblue]

After digging into emberjs/ember-test-helpers#545 a bit, I believe that the code we use to detect if ember-cli-babel's direct parent includes @ember/jquery as a dependency is a bit off (note this may also apply to @ember/string, tbd).

Specifically, we use ember-cli-version-checker to check the version of the @ember/jquery instance available from this.parent.root. Internally ember-cli-version-checker is using standard node resolution algorithm to determine the version that would be required from that root path. Since both yarn and npm@3+ use as flat of a heirarchy as possible, this means that if anyone depends on @ember/jquery throughout the system or if that module happened to be present (from a prior ember-try scenario perhaps 😸) there will be a node_modules/@ember/jquery/package.json found. I believe this is ultimately causing the bug reported in emberjs/ember-test-helpers#545...

Path forward time, I think that we should:

Check '@ember/jquery' in this.parent.dependencies() (present on both addon and project base classes) before checking for the version. If @ember/jquery is not in the parents dependencies, we would not be blacklisting.

@simonihmig - Thoughts?
@locks - Can you poke at the @ember/string side to see if this is also an issue there?