CSIT scripts have now been modified to download CSIT PIP requirements only if the libraries don't already exist system-wide, and VIRL images have been modified to include these requirements system-wide.

This eliminates repetitive download of PIP requirements on the actual SUTs and on TG.

However, Jenkins workers (where the Robot framework itself is run) do not seem to include PIP requirements system-wide, still resulting in downloads each time a test is executed.

This issue is to fix this, and install the PIP requirements as part of system libraries on Jenkins workers (and make sure they are re-installed each time a new Jenkins worker is created).