9 files declare their use of OrderAfter

AAlterHooks.php in core/modules/system/tests/modules/HookOrder/aaa_hook_order_test/src/Hook/AAlterHooks.php
AHooks.php in core/modules/system/tests/modules/HookOrder/aaa_hook_order_test/src/Hook/AHooks.php
Ckeditor5Hooks.php in core/modules/ckeditor5/src/Hook/Ckeditor5Hooks.php
HookOrderTest.php in core/tests/Drupal/KernelTests/Core/Hook/HookOrderTest.php
LayoutBuilderOverrideHook.php in core/modules/layout_builder/tests/modules/layout_builder_override_dependency/src/Hook/LayoutBuilderOverrideHook.php
TestHookAfter.php in core/modules/system/tests/modules/HookCollector/aaa_hook_collector_test/src/Hook/TestHookAfter.php
TestHookAfterClassMethod.php in core/modules/system/tests/modules/HookCollector/aaa_hook_collector_test/src/Hook/TestHookAfterClassMethod.php
TestHookOrderExtraTypes.php in core/modules/system/tests/modules/HookCollector/aaa_hook_collector_test/src/Hook/TestHookOrderExtraTypes.php
TestHookReorderHookFirst.php in core/modules/system/tests/modules/HookCollector/aaa_hook_collector_test/src/Hook/TestHookReorderHookFirst.php

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