Cargo mutants filter diff only for rust files

[benalleng]

This adds a commit onto some existing commits that we know fail ci to see if an update to cargo mutants fixes the problem

Pull Request Checklist

Please confirm the following before requesting review:

• I have disclosed my use of
  AI
  in the body of this PR.
• I have read CONTRIBUTING.md and rebased my branch to produce hygienic commits.

[benalleng]

RIP

[coveralls]

Pull Request Test Coverage Report for Build 19909489050

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 83.539%

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Totals
Change from base Build 19824041153:	0.0%
Covered Lines:	8988
Relevant Lines:	10759

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💛 - Coveralls

[benalleng]

@spacebear21 could you sanity check this one? We just want to filter the diff for .rs files anyways right?

[spacebear21]

We just want to filter the diff for .rs files anyways right?

That makes sense to me. I broke the dart workflow with a bad push to #1208, but if you rebase this PR with just your fix i'll merge it and rebase mine on top of it.

[benalleng]

I can just drop your commits to keep the history cleaner