Rebuild for python38

[regro-cf-autotick-bot]

This PR has been triggered in an effort to update python38.

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This package has the following downstream children:
songbird
And potentially more.
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[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[nsoranzo]

I suppose the issue here is that there is no Windows build of Scipy in conda-forge ( conda-forge/scipy-feedstock#80 ) and there is no py38 build of Scipy in defaults.