Replace nose with pytest

bob/bio/face/test/test_algorithms.py

bob/bio/face/test/test_baselines.py

bob/bio/face/test/test_databases.py

bob/bio/face/test/test_embeddings.py

bob/bio/face/test/test_extractors.py

bob/bio/face/test/test_picklability.py

bob/bio/face/test/test_transformers.py

conda/meta.yaml

pyproject.toml