tortuosity_gdd returns throat tortusoity values in the wrong order

[ma-sadeghi]

Currently, it returns throat tortuosity in yzx order, rather than xyz:

porespy/porespy/beta/_gdd.py

Lines 215 to 237 in 8b9c0cb

	# x direction
	network_calc(image=im,
	chunk_size=chunk_size,
	network=net,
	phase=air,
	bc=['left', 'right'],
	axis=1),
	# y direction
	network_calc(image=im,
	chunk_size=chunk_size,
	network=net,
	phase=air,
	bc=['front', 'back'],
	axis=2),
	# z direction
	network_calc(image=im,
	chunk_size=chunk_size,
	network=net,
	phase=air,
	bc=['top', 'bottom'],
	axis=0)]

@rickyfann