Replace maxdict with lru_cache

[hoodmane]

Matplotlib removed maxdict: https://matplotlib.org/stable/api/prev_api_changes/api_changes_3.6.0.html#miscellaneous-internals

I asked about this on the matplotlib discourse: https://discourse.matplotlib.org/t/matplotlib-pyodide-font-caching-with-maxdict-and-lru-cache/24260

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

:exclamation: No coverage uploaded for pull request base (main@61935f7). Click here to learn what that means.

Additional details and impacted files

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[juntyr]

What's the status of this PR?

[hoodmane]

I don't really understand matplotlib, so it's difficult to judge whether the patch is correct or not and I don't have that much faith in our test coverage. But it seems okay so we could just merge it and see if it unblocks the update. It would be nice to upstream some of the stuff but we have nobody who either understands matplotlib or wants to spend time learning about it. So it might be best just to wait until someone shows up with the inclination to maintain this.

[ryanking13]

I think we can merge and release? @hoodmane