`.tap` always assumes that the last element in the current list is a sink

[mariodruiz]

The problem is here, this append should be conditional on whether self._current_pipeline[-1] is part of the default path

https://github.com/Xilinx/PYNQ_Composable_Pipeline/blob/beb0cb6de0cd86ee3b8aaaea89ecdc7b3eecf000/pynq_composable/composable.py#L818

Also, the self._current_pipeline should not be the old pipeline