CI: --strict option in pytest failing builds
seems we are passing `--strict` to pytest, we must have picked up an updated version and this is now raising: https://dev.azure.com/pandas-dev/pandas/_build/results?buildId=50126&view=logs&j=eab14f69-13b6-5db7-daeb-7b778629410b&t=ce687173-08c6-5301-838d-71b2dda24510

temporarily can just fix the pytest version or just remove this 

cc @pandas-dev/pandas-core 