performance(tests): Using the mimalloc feature for cairo-test on testing.

[orizi]

Summary

Added the mimalloc feature flag to the Cairo test runner in the CI workflow to improve memory allocation performance.

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Type of change

Please check one:

• Bug fix (fixes incorrect behavior)
• New feature
• Performance improvement
• Documentation change with concrete technical impact
• Style, wording, formatting, or typo-only change

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Why is this change needed?

The Cairo test runner can benefit from using the mimalloc memory allocator, which generally provides better performance characteristics than the default system allocator. This change enables the mimalloc feature in CI, which should result in faster test execution and potentially reduced memory usage.

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What was the behavior or documentation before?

Previously, the CI workflow was running Cairo tests without the mimalloc allocator:

cargo run --profile=ci-dev --bin cairo-test -- ${{ matrix.cmd }}

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What is the behavior or documentation after?

Now the CI workflow runs Cairo tests with the mimalloc allocator enabled:

cargo run --profile=ci-dev --bin cairo-test --features=mimalloc -- ${{ matrix.cmd }}

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Additional context

Mimalloc is a compact general purpose allocator with excellent performance characteristics. This change should help improve CI performance without affecting test behavior.

[reviewable-StarkWare]

This change is 

[orizi]

• performance(tests): Using the mimalloc feature for cairo-test on testing. #9478 👈 (View in Graphite)
• performance(cairo-execute): Removed mimalloc dependency preventing workspace-level feature unification. #9477
• main

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[eytan-starkware]

@eytan-starkware reviewed 1 file and all commit messages, and made 1 comment.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @orizi).