fix: correct pd/ppd/tfn/tmod completion doc

https://github.com/rust-analyzer/rust-analyzer/blob/a33eefa3b26000b3018e6bb873f18dbe15ab4ab7/crates/ra_ide/src/completion/complete_snippet.rs#L23

Author: fannheyward

crates/ra_ide/src/completion.rs

@@ -63,19 +63,19 @@ pub use crate::completion::{
 // There also snippet completions:
 //
 // .Expressions
-// - `pd` -> `println!("{:?}")`
-// - `ppd` -> `println!("{:#?}")`
+// - `pd` -> `eprintln!(" = {:?}", );")`
+// - `ppd` -> `eprintln!(" = {:#?}", );`
 //
 // .Items
-// - `tfn` -> `#[test] fn f(){}`
+// - `tfn` -> `#[test] fn feature(){}`
 // - `tmod` ->
 // ```rust
 // #[cfg(test)]
 // mod tests {
 //     use super::*;
 //
 //     #[test]
-//     fn test_fn() {}
+//     fn test_name() {}
 // }
 // ```