[clang] [clang] Do not infer lifetimebound for functions with void return type (PR #131997)

[Ilya Biryukov via cfe-commits]

ilya-biryukov wrote:

LGTM!
I second the suggestion to add a test. Also see the suggestion to turn this into a warning in the first place: https://github.com/llvm/llvm-project/issues/126231#issuecomment-2735876367

I am not sure why lifetimebound needs to be an error while other attributes like `const` produce a warning and can be ignored.

https://github.com/llvm/llvm-project/pull/131997