Sportec end_coordinates incorrect

[UnravelSports]

It seems that "X/Y-Source-Position" in Sportec are the coordinates of the first touch (aka, the receive coordinates). These are currently parsed incorrectly, because in Kloppy we use the "event.receiver_coordinates" coordinates to mean pass_end_coordinates to then translate them into "END_COORDINATES_X/Y" because other providers provide end coordinates with passes instead of, let's say, start coordinates.

Now, because of this we would need to shift the receiver coordinates up by 1 in order to assign them as end_coordinates of the previous pass.

For example, at kick-off the Source-Position are equal to the Position coordinates. The pass after the kick-off then has Source-Position that should be assigned to the kick-off as being the kick-offs end coordinates.