Move higher-ranked-trait-bounds tests into higher-ranked subdir

tests/ui/README.md

@@ -687,10 +687,6 @@ See:
 - [Higher-ranked trait bounds | rustc-dev-guide](https://rustc-dev-guide.rust-lang.org/traits/hrtb.html)
 - [Higher-ranked trait bounds | Nomicon](https://doc.rust-lang.org/nomicon/hrtb.html)
 
-## `tests/ui/higher-ranked-trait-bounds`
-
-**FIXME**: move to `tests/ui/higher-ranked/trait-bounds`
-
 ## `tests/ui/hygiene/`
 
 This seems to have been originally intended for "hygienic macros" - macros which work in all contexts, independent of what surrounds them. However, this category has grown into a mish-mash of many tests that may belong in the other directories.

tests/ui/higher-ranked/trait-bounds/higher-trait-bounds-ice-60218.rs

@@ -1,6 +1,4 @@
-// https://github.com/rust-lang/rust/issues/60218
-// Regression test for #60218
-//
+// Regression test for https://github.com/rust-lang/rust/issues/60218
 // This was reported to cause ICEs.
 
 use std::iter::Map;

tests/ui/higher-ranked/trait-bounds/higher-trait-bounds-ice-60218.stderr

@@ -1,5 +1,5 @@
 error[E0277]: the trait bound `&u32: Foo` is not satisfied
-  --> $DIR/higher-trait-bounds-ice-60218.rs:19:19
+  --> $DIR/higher-trait-bounds-ice-60218.rs:17:19
    |
 LL |     trigger_error(vec![], |x: &u32| x)
    |     ------------- ^^^^^^ the trait `Foo` is not implemented for `&u32`
@@ -7,12 +7,12 @@ LL |     trigger_error(vec![], |x: &u32| x)
    |     required by a bound introduced by this call
    |
 help: this trait has no implementations, consider adding one
-  --> $DIR/higher-trait-bounds-ice-60218.rs:8:1
+  --> $DIR/higher-trait-bounds-ice-60218.rs:6:1
    |
 LL | pub trait Foo {}
    | ^^^^^^^^^^^^^
 note: required by a bound in `trigger_error`
-  --> $DIR/higher-trait-bounds-ice-60218.rs:14:72
+  --> $DIR/higher-trait-bounds-ice-60218.rs:12:72
    |
 LL | pub fn trigger_error<I, F>(iterable: I, functor: F)
    |        ------------- required by a bound in this function