Error: Cannot find module 'node:process'; Only supports 14.18.0 or newer

When updating jsonld from 5.2.0 to 6.0.0, we started getting the following error when running our tests:

Error: Jest: Got error running globalSetup - C:\repos\project\jest.setup.js, reason: Cannot find module 'node:process'
Require stack:
- C:\repos\project\node_modules\@digitalbazaar\http-client\dist\cjs\index.cjs        
- C:\repos\project\node_modules\jsonld\lib\documentLoaders\node.js
- C:\repos\project\node_modules\jsonld\lib\platform.js
- C:\repos\project\node_modules\jsonld\lib\jsonld.js
- C:\repos\project\node_modules\jsonld\lib\index.js
...

This happened when using Node 14.16.1.

Apparently Node didn't start supporting the node: prefix syntax until v16.0.0 and 14.18.0. See the history section at https://nodejs.org/dist/latest-v18.x/docs/api/modules.html#core-modules.

The GitHub actions for this project are being run with 14.19.2 according to https://github.com/digitalbazaar/http-client/runs/6513550578 and newer runs.

So, the project really only supports v14.18.0 or above; not 14.x.

I think removing the node: prefix would then allow all versions of node v14 to be supported, unless there is something else incompatible too.

Start by locating the node:process usage implicated by the @digitalbazaar/http-client stack and check how Node versions are declared for the project. Reproduce the failure on Node 14.16.1, then run the test suite on Node 14.18.0 or newer. Done means Node 14.16.1 no longer fails with Cannot find module 'node:process' without breaking newer Node runs.