Add dask array compatibility layer

[jni]

cc @GenevieveBuckley

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[jni]

TODO: add tests to ensure results are unchanged between numpy with "unique_junctions=False" and dask.

[GenevieveBuckley]

TODO:

• CI tests are failing because dask is not available in the test environment. We need dask and dask-image to be there.

[GenevieveBuckley]

I've got some bad news about the tests @jni - there's a problem besides the test environment dependencies

[jni]

This is the line that install things when running tests:

skan/.github/workflows/test.yml

Line 53 in 97a217d

pip install .[all,testing]

So dask needs to be added to:

skan/setup.cfg

Line 65 in 97a217d

testing =

[GenevieveBuckley]

Hmm, would have thought that was being handled by the all part of that. I've added dask (& dask-image) to the testing requirements in setup.cfg and we'll see how that goes.

Thanks for checking into it :)