update max sharpe notebook

[richrines1]

we exclude this one from pytest but include it in our docs, and currently it won't run correctly (due to changes in yfinance i think?)

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[bharat-thotakura]

Thanks for looking at this! LGTM % comments/questions

(was able to run the notebook locally without issue ... except the cell that calls Wikipedia, but I'm having trouble with Wikipedia outside of this notebook anyway so most likely not universal)