Update grid.cc #545

Job	Run time
testmode ON / classicmode_1d_3dgrid	20m 0s
testmode ON / classicmode_3d	22m 4s
testmode ON / kilonova_1d_1dgrid	10m 7s
testmode ON / kilonova_1d_3dgrid	10m 34s
testmode ON / kilonova_2d_2dgrid	17m 58s
testmode ON / kilonova_2d_2dgrid_barnesthermalisation	16m 34s
testmode ON / kilonova_2d_2dgrid_expansionopac	13m 26s
testmode ON / kilonova_2d_2dgrid_xcomgammaphotoion	15m 3s
testmode ON / kilonova_2d_3dgrid	19m 28s
testmode ON / nebular_1d_3dgrid	26m 38s
testmode ON / nebular_1d_3dgrid_limitbfest	28m 10s
testmode ON / combine_checksums	0s
	3h 20m 2s

Provide feedback