lookup: add debug

[targos]

Hard Requirements:

• Module source code must be on Github.
• Published versions must include a tag on Github
• The test process must be executable with only the commands npm install && npm test or (yarn install && yarn test) using the tarball downloaded from the Github tag mentioned above
• The tests pass on supported major release lines
• The maintainers of the module remain responsive when there are problems
• At least one module maintainer must be added to the lookup maintainers field

Soft Requirements:

• The module must be actively used by the community OR
• The module must be heavily depended on OR

[targos]

CI (pending): https://ci.nodejs.org/view/Node.js-citgm/job/citgm-smoker-pipeline/51/console

[targos]

New CI: https://ci.nodejs.org/view/Node.js-citgm/job/citgm-smoker-pipeline/52/

[mcollina]

LGTM

[targos]

I'm going to skip Windows. I can reproduce the failure with a local clone of the repo. Also IBM platforms because of PhantomJS.