docs(finalizer): fix typo

Closes #48916

GitOrigin-RevId: c95211d
Change-Id: Ic44b2bf80f4bb21056b5a671b6d047381928c87e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/242900
Reviewed-by: Kevin Moore <[email protected]>
Reviewed-by: Slava Egorov <[email protected]>
Commit-Queue: Slava Egorov <[email protected]>
Commit-Queue: Kevin Moore <[email protected]>

Author: SkinnyMind

sdk/lib/core/weak.dart

@@ -173,7 +173,7 @@ abstract class Finalizer<T> {
 
   /// Attaches this finalizer to [value].
   ///
-  /// When [value] is longer accessible to the program,
+  /// When [value] is no longer accessible to the program,
   /// while still having an attachement to this finalizer,
   /// the callback of this finalizer *may* be called
   /// with [finalizationToken] as argument.