Add support for Python 3.10

[tamargrey]

Closes #1803

[tamargrey]

Not sure we can actually do this since 3.10 isn't supported by koalas and we use koalas in our docs. Woodwork only runs the docs build for 3.8 in its CI. Is it better to match Woodwork and only run on 3.8 or have all but 3.10 be run?

[gsheni]

Have all but 3.10 run (since its not slowing us down, and increase our testing scenarios).

[gsheni]

Do we need to put a note somewhere in the docs that 3.10 isn't support for Koalas (yet)?

[rwedge]

That also means the 3.10 unit tests koalas run is pretty much useless

Can we look into excluding them from the test runs?

Not exactly what we want but gives an idea:
https://github.community/t/how-to-conditionally-include-exclude-items-in-matrix-eg-based-on-branch/16853/6

[tamargrey]

Seems like we would want to add

      exclude:
        - python_version: "3.10"
        - libraries: "koalas"

if im understanding correctly

[tamargrey]

90a255c

oops

[Invalid workflow file: .github/workflows/unit_tests_with_latest_deps.yml#L18](https://github.com/alteryx/featuretools/actions/runs/1959930281/workflow)
The workflow is not valid. .github/workflows/unit_tests_with_latest_deps.yml (Line: 18, Col: 7): Unexpected value 'exclude'

[rwedge]

I think it would be

exclude:
  - python_version: "3.10"
    libraries: "koalas"

https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#example-excluding-configurations-from-a-matrix

[rwedge]

using a dash mark for each would exclude all 3.10, and all koalas

[tamargrey]

that is indeed what happened 🤦‍♀️ thank you!

[codecov]

Codecov Report

Merging #1940 (173c575) into main (ef89147) will not change coverage.
The diff coverage is n/a.

❗ Current head 173c575 differs from pull request most recent head f1aa760. Consider uploading reports for the commit f1aa760 to get more accurate results

@@           Coverage Diff           @@
##             main    #1940   +/-   ##
=======================================
  Coverage   98.99%   98.99%           
=======================================
  Files         146      146           
  Lines       16438    16438           
=======================================
  Hits        16273    16273           
  Misses        165      165           

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[gsheni]

looks good assuming tests pass and my 1 suggestion is applied.