Require ignore 0.4.24 in `Cargo.toml` (#21292)
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Since 4c4ddc8c29e, ruff uses the `WalkBuilder::current_dir` API
[introduced in `ignore` version
0.4.24](https://diff.rs/ignore/0.4.23/0.4.24/src%2Fwalk.rs), so it
should explicitly depend on this minimum version.
See also https://github.com/astral-sh/ruff/pull/20979.
## Test Plan
<!-- How was it tested? -->
Source inspection verifies this version is necessary; no additional
testing is required since `Cargo.lock` already has (at least) this
version.
