Development: always use webpack on development (#12182)
The Docker development environment always starts the `webpack` container
since we removed the legacy dashboard.
This PR makes the `webpack` server to be used by default when calling
`inv docker.up`.
<!-- readthedocs-preview docs start -->
---
:books: Documentation previews :books:
- User's documentation (`docs`):
https://docs--12182.org.readthedocs.build/12182/
<!-- readthedocs-preview docs end -->
<!-- readthedocs-preview dev start -->
- Developer's documentation (`dev`):
https://dev--12182.org.readthedocs.build/12182/
<!-- readthedocs-preview dev end -->
