`#[error()]` Upgrade from 1.0 to 2.0 error:#414

```rust use crate::avutil::err2str; #[non_exhaustive] #[derive(thiserror::Error, Debug, Eq, PartialEq)] pub enum RsmpegError { #[error("AVERROR({0}): `{}`", err2str(*.0).unwrap_or_else(|| "Unknown error code.".to_string()))] AVError(c_int), } ``` 1.0 is ok. 2.0 Compile Error： ```text error: ambiguous reference to positional arguments by number in a tuple variant; change this to a named argument --> src/error.rs:14:35 | 14 | #[error("AVERROR({0}): `{}`", err2str({0}).unwrap_or_else(|| "Unknown error code.".to_string()))] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ```