"Node on Pages" provides incorrect information on how builds work

[drewbo]

Our documentation provides conflicting information on how node dependencies are handled:

...the Pages build engine will check for a package.json file. If it finds one, it will install npm dependencies...

and

Pages runs npm ci which means: Your project must have a package-lock.json file

We actually won't run the install unless the lock file is present (https://github.com/cloud-gov/pages-build-container/blob/main/src/steps/build.py#L188-L207). It's possible this logic (which is notably a bit sloppy as written) was changed during the caching implementation

Notes

• https://cloud.gov/pages/documentation/node-on-pages/#the-pages-npm-script

Acceptance Criteria

• Determine next steps and acceptance criteria