@ogerly the maintenance page needs just two components of the webapp
folder. For that reason we import only these. If you add imports to
`LocaleSwitch` component, you need to copy those files in the
Dockerfile.
This will install the dependencies of the webapp/ folder first and then
overwrite the package.json to use different scripts. If we would track
dependencies in a separate package.json we would have to update it
with dependabot. We don't want that because of our precious build
server time.
