Reword sentence

Author: estebank

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -481,7 +481,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                                 // couldn't be met.
                                 err.span_note(
                                     relevant_bindings,
-                                    format!("unmet `{sub}` obligations introduced here"),
+                                    format!("`{sub}` requirement introduced here"),
                                 );
                             }
                         }

tests/ui/lifetimes/point-at-lifetime-obligation-from-trait-in-trait-object.stderr

@@ -10,7 +10,7 @@ note: lifetime parameter instantiated with the lifetime `'a` as defined here
 LL | struct Something<'a> {
    |                  ^^
    = note: but lifetime parameter must outlive the static lifetime
-note: unmet `'static` obligations introduced here
+note: `'static` requirement introduced here
   --> $SRC_DIR/core/src/any.rs:LL:COL
 
 error: aborting due to 1 previous error