Copying GenotypeDaskArray returns DaskArray

[travc]

GenotypeDaskArray.copy() returns a DaskArray
Doesn't seem quite right... and it is breaking some of my code.

print('numpy', np.__version__)
print('allel', allel.__version__)
print('zarr', zarr.__version__)

print(type(all_g))
g = all_g.copy()
print(type(g))

numpy 1.22.3
allel 1.3.5
zarr 2.11.1
<class 'allel.model.dask.GenotypeDaskArray'>
<class 'dask.array.core.Array'>