Remove obsolete ordered-set requirement

[mgorny]

FWICS ordered-set was inlined into this package, so remove the stale requirement.

[Erotemic]

LGTM, merge when the dashboards pass

[codecov[bot]]

Codecov Report

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

Project coverage is 97.03%. Comparing base (d894785) to head (3c26e8f). Report is 405 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #108 +/- ## =========================================== - Coverage 100.00% 97.03% -2.97% =========================================== Files 28 28 Lines 3003 3001 -2 Branches 604 588 -16 =========================================== - Hits 3003 2912 -91 - Misses 0 82 +82 - Partials 0 7 +7 ```

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[Erotemic]

@mgorny Can you look into whatever is causing the coverage to go down?

[mgorny]

@mgorny Can you look into whatever is causing the coverage to go down?

My guess would be a race condition between multiple parallel jobs uploading coverage for different Python versions. You're trying to combine coverage from multiple runs but since every job is run in a separate environment, it just "combines" that one file and uploads it.

I'm pretty sure that there is a way to create an extra job that would be run after all test jobs finish but I don't know if it's possible to copy files from test jobs to another job for merging.

[Erotemic]

Hmm, I thought I accounted for that, but perhaps not. This is simple enough I'm fine with just merging it and we can see if the issue persists on main. If so, I'll need to clean it up before a release.

[mgorny]

Thanks!