👌 IMPROVE: [code load] Enable utf-8 as the standard encoding for reading code from files

[mmcky]

It looks like windows platform doesn't by default always use utf-8 when reading text from files. I think this is a sensible cross-platform default.

QuantEcon/lecture-python.myst#144

There is also a related issue reported on stackoverflow

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.43%. Comparing base (e39132e) to head (c234bae).
⚠️ Report is 203 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #332   +/-   ##
=======================================
  Coverage   87.43%   87.43%           
=======================================
  Files          12       12           
  Lines        1337     1337           
=======================================
  Hits         1169     1169           
  Misses        168      168           

Flag	Coverage Δ
pytests	87.43% <100.00%> (ø)

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[bsipocz]

This looks reasonable to me, but the code has been refactored enough in the past few years that it needs some fixing up.

Would you @mmcky be interested of resurrecting it? Unfortunately I don't see the old CI status any more to figure out the reason why it got the "on hold" label and draft status, if it's too much work to fix up this PR I would recommend to close it and open an issue for tracking the problem.