Choose the step to build in the docker image

[lunika]

Feature Request

Is your feature request related to a problem or unsupported use case? Please describe.

In development we not need to build entirely the docker image. Only the backend image is needed, the front one is not needed because we use a shared volume in the docker-compose file.

Describe the solution you'd like

We would like to choose the steps to build and also skip all the collecstatic work.
Building the entire image must still be available and tested in the CI.