Suboptimal suggestion from implied_bounds_in_impls when adding bounds to associated type

Summary

When returning a type with redundant bounds on an associated type, implied_bounds_in_impls's suggestion duplicates the implied bound

Reproducer

I tried this code (playground]:

<pub trait MyTrait {
    type MyAssociatedType;
}

pub trait MyStricterTrait: MyTrait<MyAssociatedType: Clone> {}

pub struct MyStruct;
pub struct MyStruct2;

impl MyTrait for MyStruct {
    type MyAssociatedType = u64;
}

impl MyTrait for MyStruct2 {
    type MyAssociatedType = Vec<u64>;
}

impl MyStricterTrait for MyStruct {
}

pub fn f() -> impl MyStricterTrait + MyTrait<MyAssociatedType: Copy> {
    MyStruct
}

I expected to see this happen:

warning: this bound is already specified as the supertrait of `MyStricterTrait`
  --> src/lib.rs:21:38
   |
21 | pub fn f() -> impl MyStricterTrait + MyTrait<MyAssociatedType: Copy> {
   |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implied_bounds_in_impls
   = note: `#[warn(clippy::implied_bounds_in_impls)]` on by default
help: try removing this bound
   |
21 - pub fn f() -> impl MyStricterTrait + MyTrait<MyAssociatedType: Copy> {
21 + pub fn f() -> impl MyStricterTrait<MyAssociatedType: Copy> {
   |

Instead, this happened:

warning: this bound is already specified as the supertrait of `MyStricterTrait`
  --> src/lib.rs:21:38
   |
21 | pub fn f() -> impl MyStricterTrait + MyTrait<MyAssociatedType: Copy> {
   |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#implied_bounds_in_impls
   = note: `#[warn(clippy::implied_bounds_in_impls)]` on by default
help: try removing this bound
   |
21 - pub fn f() -> impl MyStricterTrait + MyTrait<MyAssociatedType: Copy> {
21 + pub fn f() -> impl MyStricterTrait<MyAssociatedType: Copy> + MyTrait<MyAssociatedType: Copy> {
   |

Version

default versions on the Rust playground (rustc 1.82.0)

Additional Labels

No response

Start by running the linked Rust Playground reproducer with the implied_bounds_in_impls lint enabled and compare the actual suggestion with the expected one. Locate the lint implementation and its suggestion-building entry point, then verify the result against this associated-type bound case. Done means the diagnostic removes the redundant bound without duplicating it.