clippy --fix now errors on untracked files

Summary

After upgrading to rust 1.67.0 clippy --fix now fails if you have any untracked files in your git repository. I now have to pass the --allow-dirty flag to use clippy --fix. I didn't have to do this in rust 1.66.0.

If this is a deliberate change, I suggest adding an --allow-untracked flag to clippy --fix so that we can get the old behavior back.

Reproducer

reproduce:

cargo new foo
cd foo
git add .
git commit -m "Initial commit"
touch bar.txt
cargo clippy --fix

I expected to see this happen: Success

Instead, this happened:

error: the working directory of this package has uncommitted changes, and `cargo fix` can potentially perform destructive changes; if you'd like to suppress this error pass `--allow-dirty`, `--allow-staged`, or commit the changes to these files:

  * bar.txt (dirty)

Version

rustc 1.67.0 (fc594f156 2023-01-24)
binary: rustc
commit-hash: fc594f15669680fa70d255faec3ca3fb507c3405
commit-date: 2023-01-24
host: x86_64-unknown-linux-gnu
release: 1.67.0
LLVM version: 15.0.6

Additional Labels

No response

Start by running the reported cargo new, git commit, touch bar.txt, and cargo clippy --fix reproducer with Rust 1.67.0, then inspect the clippy --fix handling related to dirty and untracked files. Confirm the behavior against Rust 1.66.0 and define done as restoring the expected success or providing the requested way to allow untracked files without allowing other dirty changes.