Add update checker

[jeff-hernandez]

Closes #2333 by adding the Alteryx open-source update checker. The update checker will automatically check if there's a newer release of EvalML available.

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #2350 (fdd50f6) into main (1111770) will not change coverage.
The diff coverage is 100.0%.

@@          Coverage Diff          @@
##            main   #2350   +/-   ##
=====================================
  Coverage   99.7%   99.7%           
=====================================
  Files        283     283           
  Lines      25233   25233           
=====================================
  Hits       25133   25133           
  Misses       100     100           

Impacted Files	Coverage Δ
evalml/__init__.py	100.0% <100.0%> (ø)

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[angela97lin]

Just to make sure I understand the purpose of this: this is supposed to check that the packages evalml depends on are up to date? From the README, it sounded like it would automatically download the latest version of evalml but I tried to purposely downgrade evalml (to 0.24.0) an run python -m pip install evalml[update_checker] and nothing happened?

[gsheni]

@angela97 this will only work once it is merged into main and released. In addition, it will only work with versions of EvalML going forward. The way this would work is the following.

1. Have EvalML + updated checker installed
2. New version of EvalML comes out
3. The open-src-update-checker puts a warning in the console/output when you import evalml

[angela97lin]

@gsheni Got it, thank you for explaining! I wonder if there's a clearer way to express this in the README, but otherwise this looks good! Thanks @jeff-hernandez for doing this 😁

[gsheni]

@jeff-hernandez One thing I just realized, we should add this to the Install page

• https://evalml.alteryx.com/en/latest/install.html

[dsherry]

@jeff-hernandez looks great! One blocking change: please move the python code to evalml/utils/

I also left a comment for @freddyaboulton and @chukarsten to dig into--they've been working on our CI recently. But that's not blocking merge

[dsherry]

Thanks @jeff-hernandez looks great! Left two docs nit-picks but not blocking merge

[dsherry]

Mega nit-pick but elsewhere in our docs we say pip install ... instead of python -m pip install ...

[dsherry]

Same nit-pick as above