Conda install ignores pandas version requirements

[AdamOrmondroyd]

Describe the bug
Early this morning, conda updated to pandas 2.2.1. When #364 was merged, conda installed this version of pandas, despite the restriction in pyproject.toml to "pandas>=2.0.0,<2.2.0".

To Reproduce
Run the conda CI.

Expected behavior
An earlier, compatible version of pandas is installed by conda, and all tests pass

Screenshots

Additional context
Add any other context about the problem here.