Remove Pytorch NFSP due to indications that it is buggy and lack of maintenance.

Resolves: #1008.
PiperOrigin-RevId: 582676107
Change-Id: I622a815880c18a535f8bec83311355f2ba025c8b

Author: lanctot

open_spiel/python/CMakeLists.txt

@@ -280,7 +280,6 @@ if (OPEN_SPIEL_ENABLE_PYTORCH)
   set(PYTHON_TESTS ${PYTHON_TESTS}
       pytorch/rcfr_pytorch_test.py
       pytorch/dqn_pytorch_test.py
-      pytorch/nfsp_pytorch_test.py
       pytorch/deep_cfr_pytorch_test.py
       pytorch/eva_pytorch_test.py
       pytorch/losses/rl_losses_pytorch_test.py