Update Github Actions workflow to the lastes from API
Update Github Actions workflow to the lastes from API

This copies the Github Actions workflow from the Pelias API project.

It brings in a few notable changes:
- Run all tests against Node.js 12, 14, and 16
- Remove MacOS build jobs (they're 10x the cost, which could hurt anyone
  running these on private forks)
- Update jobs to run on Ubuntu 20 (Ubuntu 16 is deprecated:
  https://github.blog/changelog/2021-04-29-github-actions-ubuntu-16-04-lts-virtual-environment-will-be-removed-on-september-20-2021/)
- Run docker build _after_ any NPM publish, so that versioned docker
  images can be built

pelias/whosonfirst,pelias/whosonfirst