[clang-tools-extra] [clang-tidy]bugprone-unused-return-value ignore `++` and `--` operator overloading (PR #84922)

[Congcong Cai via cfe-commits]

HerrCai0907 wrote:

> Should this check really ignore postfix increment/decrement? Or maybe this check ignores it and a new check diagnoses `it++` vs `++it` (where possible). What are your thoughts on this?

@5chmidti  What does `a new check diagnoses `it++` vs `++it` (where possible)` mean?

https://github.com/llvm/llvm-project/pull/84922