Consider adding #[must_use] to std::process::Child #70186
Description
I fixed a bug that was caused by not calling .wait() on a std::process::Child. See the issue for the details. I'm not exactly sure how the bug manifested itself, but I noticed that not waiting for the child process whose stdin or stdout is inherited from the parent process can lead to weird behavior.
That's why I suggest to add #[must_use = "this Child may still be attached to its parent process's stdin/stdout and must be handled"] to std::process::Child. Currently I can't think of a reason why someone would not use a Child and that's I think the compiler warnings on that will prevent more headaches than they will cause.