CI: Rust 1.98 Clippy lints break rust-test

[ywskycn]

What is the problem the feature request solves?

Description

The PR Build (Linux) / ubuntu-latest/rust-test job started failing after Rust stable moved from 1.97.1 to 1.98.0.

The workflow uses RUST_VERSION: stable and runs:

cd native
cargo clippy --color=never --all-targets --workspace -- -D warnings

Rust 1.98 introduces new Clippy warnings that are treated as errors because of -D warnings.

Example failing job:

https://github.com/apache/datafusion-comet/actions/runs/32406126292/job/96546147984

A recent main run using Rust 1.97.1 passed the same rust-test job:

https://github.com/apache/datafusion-comet/actions/runs/32392348862/job/96502048719

Errors

error: using `chunks_exact` with a constant chunk size
  --> spark-expr/src/bloom_filter/spark_bit_array.rs:80:64

help: consider using `as_chunks::<8>()` instead

error: manual implementation of `isolate_lowest_one`
  --> spark-expr/src/nondetermenistic_funcs/internal/mersenne.rs:152:12

help: consider using `.isolate_lowest_one()`

Notes

Comet declares rust-version = "1.88" in native/Cargo.toml.

The as_chunks::<8>() suggestion is compatible with Rust 1.88.

However, isolate_lowest_one() is only available since Rust 1.97, so applying that suggestion directly would raise the effective MSRV. A targeted Clippy allow/comment or MSRV-aware Clippy configuration may be preferable.

This appears to be a repo-wide CI issue rather than a regression from any specific PR.

Describe the potential solution

No response

Additional context

No response