The issue is your Jenkins build server is unable to locate the reactotron-core-client module which is necessary to complete your Jenkins build. You can see this from your stack trace:
Unable to resolve module reactotron-core-client
The recommended solution from the npm team of:
rm -rf node_modules && npm install
is a generic solution because this command will remove your previous node_modules directory containing your project's dependencies and then reinstall the listed dependencies within in your project's package.json file. This may resolve issues stemming from your lock file as well as versioning issues if npm has been updated on your build server.
This solution may resolve your issue if all of your project's required libraries are listed within your package.json file. However, if the reactotron-core-client library isn't listed as a required dependency within your package.json file this problem will persist moving forward. Perhaps you could try the following:
npm i --save reactotron-core-client
as this will save and install the reactotron-core-client dependency for your project. By save I mean list this library as dependency within your package.json file.
Ideally, moving forward your best bet is to keep your package.json file up-to-date with your project's dependencies as well as installing dependencies prior to attempting a Jenkins build.
Hopefully that helps!
