Server CI sometimes fails to build webapp after dependency upgrade

When the server's CI tries to include the web app, it tries to pull the web app code from a matching branch's build uploaded to S3. If that doesn't exist because a build is in progress, it checks out the web app repo and tries to build it itself.

In the case where it's building the web app itself, that started failing with the dependency upgrades due to a Node error because the server is still building the web app using Node 8 for some reason. That needs to be fixed to match the web app build.