Static resources fail to build when NODE_ENV=production

The instructions here do not work:

https://github.com/metabrainz/musicbrainz-server/blob/f1584a03e1da6870891ece1b78d4d7d82ab85557/INSTALL.md#building-static-web-resources

The build fails with the following error:

[91m/workspace/build/opt/mbz-slave/node_modules/webpack-cli/bin/cli.js:231
				throw err;
				^Error: Cannot find module 'terser-webpack-plugin' 

Removing NODE_ENV=production cause the build to complete successfully. I haven't investigated too far but it seems that terser-webpack-plugin is not just a dev dependency.