[objective_c] Fix build hook

[dcharkes]

Potentially closes #2824

[coveralls]

coverage: 81.969%. remained the same
when pulling fe3d8a8 on objc-build-hook
into 93039d7 on main.

[github-actions]

PR Health

License Headers ✔️

// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

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no missing headers

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Unrelated files missing license headers

Files
pkgs/objective_c/example/command_line/lib/main.dart
pkgs/objective_c/lib/src/ns_input_stream.dart

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API leaks ⚠️

The following packages contain symbols visible in the public API, but not exported by the library. Export these symbols or remove them from your publicly visible API.

Package	Leaked API symbol	Leaking sources
objective_c	_FinalizablePointer	internal.dart::_ObjCReference::new::_finalizable

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Breaking changes ✔️

Package	Change	Current Version	New Version	Needed Version	Looking good?
objective_c	None	9.2.0	9.2.0+1	9.2.0	✔️

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Changelog Entry ✔️

Package	Changed Files

Changes to files need to be accounted for in their respective changelogs.

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