Add local repository creation facility

This local repository is stored inside the docker container, we can have
same arch or multi-arch components. It's picking the corresponding version at
the image creation time to ensure we can install them inside the container and
offline.

Use a subdirectory for the android-studio dependencies and add the needed
packages there.
Add the local repository if needed

The local repository is added only if the right arguments are given in the
medium tests class. Add this subrepository and make it a local test.