Vapor–Liquid Equilibrium for the Binary Systems 1,1,2,3,3,3-Hexafluoro-1-propene (R1216) + 2,3,3,3-Tetrafluoroprop-1-ene (R1234yf) and 1,1,2,3,3,3-Hexafluoro-1-propene (R1216) + trans-1,3,3,3-Tetrafluoropropene (R1234ze(E))