Adjust note wording

Author: jieyouxu

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -1012,7 +1012,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         );
 
         err.note(format!(
-            "the caller chooses the type of {} which can be different from {}",
+            "the caller chooses a type for `{}` which can be different from `{}`",
             expected_ty_as_param.name, found
         ));
     }

tests/ui/return/return-impl-trait-bad.stderr

@@ -53,7 +53,7 @@ LL |     "don't suggest this, because the generic param is used in the bound."
    |
    = note: expected type parameter `T`
                    found reference `&'static str`
-   = note: the caller chooses the type of T which can be different from &'static str
+   = note: the caller chooses a type for `T` which can be different from `&'static str`
 
 error: aborting due to 4 previous errors
 

tests/ui/return/return-impl-trait.stderr

@@ -12,7 +12,7 @@ LL |     ()
    |
    = note: expected type parameter `T`
                    found unit type `()`
-   = note: the caller chooses the type of T which can be different from ()
+   = note: the caller chooses a type for `T` which can be different from `()`
 
 error[E0308]: mismatched types
   --> $DIR/return-impl-trait.rs:23:5
@@ -29,7 +29,7 @@ LL |     ()
    |
    = note: expected type parameter `T`
                    found unit type `()`
-   = note: the caller chooses the type of T which can be different from ()
+   = note: the caller chooses a type for `T` which can be different from `()`
 
 error: aborting due to 2 previous errors