fix: pin dask version to 2024.12.1 (ecmwf#94)

* pin dask

* add comment

* support version <= 2024.12.1

Author: JPXKQX

training/pyproject.toml

@@ -44,6 +44,7 @@ dependencies = [
   "anemoi-graphs>=0.4.1",
   "anemoi-models>=0.4.1",
   "anemoi-utils[provenance]>=0.4.4",
+  "dask<=2024.12.1",                 # pinned until a new datashader version is released
   "datashader>=0.16.3",
   "einops>=0.6.1",
   "hydra-core>=1.3",