Rollup merge of #148506 - estebank:issue-41966, r=davidtwco

Special case detecting `'static` lifetime requirement coming from `-> Box<dyn Trait>`

```
error[E0310]: the parameter type `R` may not live long enough
  --> $DIR/implicit-static-lifetime-in-dyn-trait-return-type.rs:10:5
   |
LL | fn bb<R>(r: R) -> Box<dyn Foo> {
   |                       ------- this `dyn Trait` has an implicit `'static` lifetime bound
LL |     Box::new(Bar(r))
   |     ^^^^^^^^^^^^^^^^
   |     |
   |     the parameter type `R` must be valid for the static lifetime...
   |     ...so that the type `R` will meet its required lifetime bounds
   |
help: consider adding an explicit lifetime bound
   |
LL | fn bb<R: 'static>(r: R) -> Box<dyn Foo> {
   |        +++++++++
```

Partly address rust-lang/rust#41966 and rust-lang/rust#54753. rust-lang/rust#103849, which shows a case where there's an intermediary binding, is not addressed at all, as aren't cases *other* than `Box<dyn Trait>` return type.

Author: Zalathar