Rollup merge of #131757 - c6c7:fixup-lint-non-snake-case-crate, r=jieyouxu

Ignore lint-non-snake-case-crate#proc_macro_ on targets without unwind

The lint-non-snake-case-crate test may emit a warning in stderr if the target does not support unwinding

```
warning: building proc macro crate with `panic=abort` may crash the compiler should the proc-macro panic
```

Consequently, the test will fail on targets that don't support unwinding as written.

This change modifies the expected stderr for lint-non-snake-case-crate in the proc_macro_ to ignore lines that indicate a warning was emitted.

Author: matthiaskrgr