Pass axis metadata for ome.zarr

[constantinpape]

We need to ensure that the axis metadata can be passed correctly to ome.zarr files. This can be passed via metadata_dict https://github.com/constantinpape/cluster_tools/blob/master/cluster_tools/downscaling/downscaling_workflow.py#L19.
But I am not sure if this is correctly working for the ome.zarr axis metadata.