Fix flaky GELU test and clippy warnings in candle-onnx

[Douglas-Nyberg]

Changes

• Fix test_gelu_operation in candle-onnx to use approximate float comparison (was failing due to precision differences).
• Fix clippy warnings in candle-onnx/src/eval.rs.
• Add clippy allow attributes for pre-existing test issues (excessive float precision) and generated protobuf code.

Why

While running tests locally, I found that test_gelu_operation was flaky due to using exact float equality. Additionally, cargo clippy revealed several issues in eval.rs that needed fixing.

(Note: I originally attempted to add candle-onnx to the workspace/CI, but reverted that infrastructure change per maintainer feedback to focus solely on these code fixes.)

Testing

All 64 candle-onnx tests pass locally. cargo clippy passes.

[ivarflakstad]

Thanks!

I'm happy to merge parts of this PR, but candle-onnx is actually purposefully excluded from workspace / CI.
We'll be making some changes to candle-core (soon ™️ ) which should make it much easier to maintain candle-onnx (and candle-pyo3). At which point we could definitely add it to workspace and CI.

[Douglas-Nyberg]

Thanks for the feedback!

I've reverted the changes to Cargo.toml and the CI workflow as requested.
This PR now only contains the code-level fixes:

Fix for the flaky GELU test: Switched to approximate comparison to handle floating point differences.
Clippy fixes: Fixed bugs in candle-onnx/src/eval.rs and added an allow attribute for the generated protobuf code.

Let me know if you would like to see something else.

[ivarflakstad]

Lgtm! Thanks :)