fix: use NODE_OPTIONS instead of calling node directly for debugging

[G-Rath]

Summary

Currently debugging options for node are handled by switching to calling node which is fine except requires the absolute path to the javascript file to execute to be passed which isn't what happens if node_modules_bin_exist? is false because that falls back to just yarn webpack and yarn webpack serve:

cmd = if node_modules_bin_exist?
  ["#{@node_modules_bin_path}/webpack", "serve"]
else
  ["yarn", "webpack", "serve"]
end

This switches to providing those options using the NODE_OPTIONS env variable instead, which should ensure the options are always enabled regardless of how the desired commands are invoked.

This change also makes #349 / #195 a little easier.

Pull Request checklist

• Add/update test to cover these changes
• Update documentation
• Update CHANGELOG file

Other Information

I have tested this locally using NODE_OPTIONS="--unhandled-rejections=warn" and having a Promise.reject() in the webpack config - I've not added any test cases since none exist already for this section, and it's a bit tricky to automate for the test suite.

[justin808]

Please change and I'll merge.