All tests don't skip python 3.9

[MichaelFu512]

Pull Request Description

Removed pytest.mark.skip_if_39 from all tests as testing them in python 3.9, none of them failed.

Did conda create -n evalml_py_39 python=3.9 then did make installdeps-dev.

After that, did a search using ctrl-f and looked for pytest.mark.skip_if_39 from all files, removed them from the files that had them and ran each tests. None of the tests that previous were skipped failed.

Only issue was two of the tests complained about not having prophet and cmdstanpy installed, but those were easily rectified by doing pip install prophet and pip install cmdstanpy.

Closes #3600

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After creating the pull request: in order to pass the release_notes_updated check you will need to update the "Future Release" section of docs/source/release_notes.rst to include this pull request by adding :pr:123.

[codecov]

Codecov Report

Merging #3602 (a9641c0) into main (931cd04) will increase coverage by 0.1%.
The diff coverage is 100.0%.

@@           Coverage Diff           @@
##            main   #3602     +/-   ##
=======================================
+ Coverage   99.7%   99.7%   +0.1%     
=======================================
  Files        335     335             
  Lines      33522   33503     -19     
=======================================
- Hits       33393   33382     -11     
+ Misses       129     121      -8     

Impacted Files	Coverage Δ
...alml/tests/component_tests/test_arima_regressor.py	100.0% <ø> (ø)
...nent_tests/test_exponential_smoothing_regressor.py	100.0% <ø> (ø)
...tests/component_tests/test_polynomial_detrender.py	100.0% <ø> (ø)
...ml/tests/component_tests/test_prophet_regressor.py	100.0% <ø> (ø)
evalml/tests/conftest.py	97.9% <ø> (+0.5%)	⬆️
.../tests/pipeline_tests/test_time_series_pipeline.py	99.9% <ø> (-<0.1%)	⬇️
evalml/tests/component_tests/test_utils.py	100.0% <100.0%> (+4.4%)	⬆️

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[eccabay]

Thanks for tackling this, it's encouraging that no tests needed to be updated! I'm wondering if we should add prophet to the dev requirements - although at the moment I don't think it's necessary.

It looks like there are a few other files that have references to skipping with python 3.9:

• evalml/tests/conftest.py
• evalml/tests/component_tests/test_utils.py

Once those are updated as well, this should be good to go!

[chukarsten]

Thanks Michael! Nice job!

[jeremyliweishih]

LGTM