Try downgrading zarr to 2.17

I think the fix for zarr-developers/zarr-python#1800 in 2.18 is what's causing the problem (why the code doesn't like it, I'm not sure) and that downgrading is the fix. We'll see...

Author: dkfellows

poetry.lock

@@ -14,7 +14,7 @@ exclude = ["hpcflow/data/demo_data"]
 
 [tool.poetry.dependencies]
 python = ">=3.9,<3.14"
-zarr = "^2.17.2"
+zarr = "~2.17.2"
 numpy = "^1.26.4"
 ruamel-yaml = "^0.18.6"
 colorama = "^0.4.6"