use Bound<'py, PyStr> str equality

[davidhewitt]

PyO3 implements direct Python to Rust str equality, which should be the most efficient pathway on any given platform.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.92%. Comparing base (8ae5b41) to head (9f04707).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #166      +/-   ##
==========================================
+ Coverage   88.90%   88.92%   +0.02%     
==========================================
  Files          13       13              
  Lines        2191     2195       +4     
  Branches     2191     2195       +4     
==========================================
+ Hits         1948     1952       +4     
  Misses        148      148              
  Partials       95       95              

Files with missing lines	Coverage Δ
crates/jiter/src/py_string_cache.rs	97.16% <100.00%> (+0.11%)	⬆️

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[codspeed-hq]

CodSpeed Performance Report

Merging #166 will improve performances by 12.37%

_{Comparing dh/py-str-eq (9f04707) with main (8ae5b41)}

Summary

⚡ 1 improvements
✅ 72 untouched benchmarks

Benchmarks breakdown

	Benchmark	main	dh/py-str-eq	Change
⚡	python_parse_string_array	26.6 µs	23.7 µs	+12.37%