Release of Gauss v49r23 for Sim09

Deploy new generators features or bug fixes to Sim09.

The version in production SimType stays Sim09k even though there is a change in a model because as-it was it could not have been used, so no productions possible.

It uses a newly released version of LHCb v39r1p8 (see below for details). Ut actually did not pick it up in cmt/project so not clear if it is used via lbstack.