lb-dev: restrict upstream project version to the requested one

The declaration of the dependency of lb-dev generated projects was selecting just a minimum version for the main project, so something like

lb-dev DaVinci/v46r0

was creating a project that was depending on at least DaVinci 46.0, which is not what we mean.

This MR fixes it so that the dependency will be on exactly DaVinci 46.0.

Closes #66 (closed)