invenio-cli containers start fails

## Describe the bug
After installing all prerequisites, when running `invenio-cli containers start --lock --build --setup` the start of the containers fails with:
```
...
Building web-ui
Sending build context to Docker daemon 19.83MB
Error response from daemon: no build stage in current context
ERROR: Service 'web-ui' failed to build : Build failed
Failed to start containerized instance.
```

## Steps to Reproduce
Follow the steps in the [InvenioRDM installation guide](https://inveniordm.docs.cern.ch/install/).

Either run `invenio-cli containers start --lock --build --setup` or `docker-compose -f docker-compose.full.yml up`, which fails with the same error

## Expected behavior
The containers successfully start.

Not sure if this is the correct place to report the bug, but at least it emerged when using `invenio-cli` trying to set up an Invenio RDM instance.

## Additional context
Apparently this is an issue with docker. Googling for the error message hints at a mistake in the `Dockerfile`, maybe a `FROM` statement is missing?

Ubuntu 21.10
Docker version 20.10.9, build c2ea9bc
docker-compose version 1.29.2, build 5becea4c
invenio-cli, version 1.0.0