Resolve rasterio & fiona dependencies

[herbiebradley]

I suggest we add an issue to resolve this compatibility issue and remember to unpin it again after (or at least give a loose requirement). It comes from a problem in the interplay between fiona and rasterio in the latest rasterio version and might already be fixed now.

Originally posted by @Croydon-Brixton in #70 (comment)

[sdat2]

Hey, I'm still having problems with rasterio when I'm trying to set up an environment for python-3.10. https://github.com/ai4er-cdt/geograph/runs/7322711709?check_suite_focus=true which corresponds to me trying to install the environment using this https://github.com/ai4er-cdt/geograph/blob/5d1a91c75bed39f65af0727123a67a729445d0fa/.github/workflows/python-package.yml.

[sdat2]

I still can't get it to work for python-3.10: https://github.com/ai4er-cdt/geograph/runs/7337125049?check_suite_focus=true , but it is working for python-3.8 and python-3.9.

[herbiebradley]

I think this compatibility issue has been solved simply by both involved packages upgrading significantly and improving their GDAL compatibility. Happy to unpin rasterio now, see #81 (comment)