[happypose_with_camera.py] Correcting a bug with the quaternion's coordinates

Change the function use to create the object's quaternion before being published in /tf. The coordinates published by happypose_with_camera were x,y,z,w. But the function transforms.matrix_to_quaternion(...) is using the w,x,y,z conformity which leads to an error in the coordinate published in /tf. I change this to use the pinocchio Quaternion function. I also change the image encoding to be sure that it correspond to the Cosypose desired one.