This PR updates our CI config to use the npm ci command to speed up our CI installs step.

This command is similar to npm-install, except it’s meant to be used in automated environments such as test platforms, continuous integration, and deployment – or any situation where you want to make sure you’re doing a clean install of your dependencies. It can be significantly faster than a regular npm install by skipping certain user-oriented features. It is also more strict than a regular install, which can help catch errors or inconsistencies caused by the incrementally-installed local environments of most npm users.

• If a node_modules is already present, it will be automatically removed before npm ci begins its install.

Which is fine now that we're not caching it anymore.