sort imports in 10 notebooks

[MarcoGorelli]

Follow-up from #4072

To get these changes I did the following:

setup.cfg:

[isort]
lines_between_types=1
no_sections=1

.nbqa.ini

[isort]
config = setup.cfg
mutate = 1

and then ran nbqa isort docs/source/notebooks/ --treat-comment-as-code '# %%'

[review-notebook-app]

Check out this pull request on 

Review Jupyter notebook visual diffs & provide feedback on notebooks.

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Powered by ReviewNB

[MarcoGorelli]

Just a note on reviewNB - if I open up the diff in there, then for docs/source/notebooks/GP-SparseApprox.ipynb it looks like this:

From this diff, it looks like there's a blank line between import pymc3 as pm and import theano. However, if I look at the new notebook here https://github.com/MarcoGorelli/pymc3/blob/next-10-notebooks/docs/source/notebooks/GP-SparseApprox.ipynb then you can see that there is no such blank line:

So, the new notebook looks correct to me, it's just the diff on ReviewNB that looks misleading (or maybe it's correct, I'm just not reading it properly 😄 )

[codecov]

Codecov Report

Merging #4073 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4073   +/-   ##
=======================================
  Coverage   88.47%   88.47%           
=======================================
  Files          88       88           
  Lines       13860    13860           
=======================================
  Hits        12263    12263           
  Misses       1597     1597           

[AlexAndorra]

Perfect, thanks @MarcoGorelli !