stackl-client should not be baked into FDI images

[mieel]

For ansible FR's to work, the images have to have stackl-client (of the correct version) installed.
This means that when the stackl host/api is updated, all FR's are required to be rebuild, published and updated in the stackl-docs.

If stackl could inject this code instead during a job container, that would make FR development much easier and upgrading stackl less tedious.