misleading "add `dyn` keyword before derive macro" suggestion

[eopb]

Given the following code: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=340b1d1f9850c0644977b8c47b00dc77

#[derive(Clone)]
struct Debug;
trait Debug {}

The current output is:

error[[E0428]](https://doc.rust-lang.org/stable/error-index.html#E0428): the name `Debug` is defined multiple times
 --> src/lib.rs:3:1
  |
2 | struct Debug;
  | ------------- previous definition of the type `Debug` here
3 | trait Debug {}
  | ^^^^^^^^^^^ `Debug` redefined here
  |
  = note: `Debug` must be defined only once in the type namespace of this module

error[[E0782]](https://doc.rust-lang.org/stable/error-index.html#E0782): trait objects must include the `dyn` keyword
 --> src/lib.rs:1:10
  |
1 | #[derive(Clone)]
  |          ^^^^^
  |
  = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)
help: add `dyn` keyword before this trait
  |
1 | #[derive(dyn Clone)]
  |          +++

Some errors have detailed explanations: E0428, E0782.
For more information about an error, try `rustc --explain E0428`.

Ideally the output should not suggest placing dyn before Clone in #[derive(Clone)] because the dyn keyword is not valid in that position.

Thank you to @conradludgate for finding the minimum reproducible that I used for this issue.

[eopb]

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