Dont suggest `use<impl Trait>` when we have an edition-2024-related borrowck issue
#131186 implements some machinery to detect in borrowck when we may have RPIT overcaptures due to edition 2024, and suggests adding `+ use<'a, T>` to go back to the edition 2021 capture rules. However, we weren't filtering out cases when there are APITs in scope.
This PR implements a more sophisticated diagnostic where we will suggest turning any APITs in scope into type parameters, and applies this to both the borrowck error note, and to the `impl_trait_overcaptures` migration lint.
cc #132809
An example directive is ignore-test. In legacy compiletest style, the header
would be written as
// ignore-test
but in ui_test style, the header would be written as
//@ ignore-test
compiletest is changed to accept only //@ directives for UI tests
(currently), and will reject and report an error if it encounters any
comments // <content> that may be parsed as an legacy compiletest-style
test header. To fix this, you should migrate to the ui_test-style header
//@ <content>.
c1f3c7078a