Fix platforms for lhcb-lcg-dev* slots
there is something wrong in the logic, see https://lhcb-nightlies.web.cern.ch/nightly/lhcb-lcg-dev3/1655/
there is something wrong in the logic, see https://lhcb-nightlies.web.cern.ch/nightly/lhcb-lcg-dev3/1655/