Updated @ember/test-helpers to 4.0.2 and added it as a peer dependency

[karl-sjogren]

@ember/test-helpers from version 4 needs to be added as a peer dependency in package.json or the following error will be shown.

@zestia/ember-dragula tried to import "@ember/test-helpers" in "@zestia/ember-dragula/test-support/helpers/simulate-drag-drop.js" from addon code, but "@ember/test-helpers" is a devDependency. You may need to move it into dependencies.

This was referenced in emberjs/ember-test-helpers#1490 in which there was a link to how they solved it in ember-scroll-modifiers. I've more or less copied their solution.

[amk221]

Thanks.

Been a while since I've given this repo any TLC.

Can you try #28

[karl-sjogren]

Sorry for the slow response @amk221, I've tried the 12.1.4-0 release and it works fine for me with both the 4.x and 3.x versions of @ember/test-helpers.

[amk221]

Thanks! Released