Release Gauss v56r0

Release for Sim10 of Gauss, should release LHCb and Run2Support as dependencies, while Gaudi, Detector and Geant4 should already be available with the correct dependencies.

Release checklist (to be filled by the shifter)

• release build validation (to be checked with the MR author)
• RPMs deployment
• CVMFS installation
• web pages update