Remove lhcb-gaudi-head-py3 and add lhcb-head-py3
- Remove lhcb-gaudi-head-py3 since
- there are no pending Gaudi-specific py3-related MRs
- +py3 platforms are available in the lhcb-gaudi-head slot
- +py3 platforms are available in the lhcb-head* slots (can be used for py3 support MRs)
- Create lhcb-head-py3
- dedicated to python 3 support MRs
- a minimal set of platforms (py2 and py3)
- all projects are included
- Do not apply lhcb-run2-patches labelled MRs to lhcb-run2-patches-py3
Edited by Rosen Matev