Draft: test overlap checker for small dRICH sensor overlaps

• disable all of the dRICH optics except for two sensors, which have a small overlap
• there is at least one such overlap per sector
• these overlaps were not identified by our CI overlap checks, so we test again here, with the dRICH restricted to being composed of 2 such overlapping sensors
• the overlaps are clearly visible in jsROOT (if you zoom in closely); see the dRICH-only subsystem view, or attached images below