Scipy version incompatibility with healpy

[ThomasCeulemans]

As of 1.14, scipy removed scipy.interpolate.trapz in favor of scipy.interpolate.trapezoid (see https://docs.scipy.org/doc/scipy/release/1.14.0-notes.html). Healpy still imports the depracted (and now removed function trapz).
Until this is fixed in healpy, I suggest manually setting the scipy version to 1.13.

[ThomasCeulemans]

Err, it seems that conda-forge as of writing has an older healpy version than pypi. I'll just set the scipy version in the conda env file to <=1.13 for now. (This will need to be reverted at some point)