Use less verbose syntax for error annotations

Co-authored-by: Esteban Kuber <estebank@users.noreply.github.com>

Author: notriddle

src/test/ui/const-generics/parser-error-recovery/issue-89013.rs

@@ -7,10 +7,10 @@ struct Bar;
 const T: usize = 42;
 
 impl Foo<N = const 3> for Bar {
-//~^ERROR expected lifetime, type, or constant, found keyword `const`
-//~^^ERROR cannot constrain an associated constant to a value
-//~^^^ERROR this trait takes 1 generic argument but 0 generic arguments
-//~^^^^ERROR associated type bindings are not allowed here
+//~^ ERROR expected lifetime, type, or constant, found keyword `const`
+//~| ERROR cannot constrain an associated constant to a value
+//~| ERROR this trait takes 1 generic argument but 0 generic arguments
+//~| ERROR associated type bindings are not allowed here
     fn do_x(&self) -> [u8; 3] {
         [0u8; 3]
     }