add MSRV of 1.73.0

[davidhewitt]

Closes #113

[codecov[bot]]

Codecov Report

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

:loudspeaker: Thoughts on this report? Let us know!

[codspeed-hq[bot]]

CodSpeed Performance Report

Merging #114 will improve performances by 10.67%

_{Comparing dh/msrv (946e093) with main (8c2cdf1)}

Summary

⚡ 1 improvements ✅ 72 untouched benchmarks

Benchmarks breakdown

	Benchmark	main	dh/msrv	Change
⚡	python_parse_string_array_not_cached	40.7 µs	36.8 µs	+10.67%