Python 3.9 and wordcloud

[rterbush]

Any chance of letting dependencies move forward to wordcloud 1.8.1? I think this would allow support of python 3.9.

[pplonski]

@rterbush thank you for pointing this. I've updated wordcloud and joblib packages and it looks that we can run AutoML on Python 3.9 :) Thank you!

Link to Travis build:
https://travis-ci.org/github/mljar/mljar-supervised/builds/763235970

I will add the next release 0.10.2 soon.