well, npm install would have installed the devDependencies too…
This sentence clicked in my brain.
I have NODE_ENV=production as default in my images (expect images I use for testing) and with this
npm installwill install nothingnpm install node-fetch@2will install nothing
so @codac please go again in the folder of the module and run NODE_ENV=test npm install node-fetch@2
this should hopefully solve the issue