11 files declare their use of ServiceModifierInterface

AcceptHeaderRoutingTestServiceProvider.php in core/modules/system/tests/modules/accept_header_routing_test/src/AcceptHeaderRoutingTestServiceProvider.php
ContainerRebuildTestServiceProvider.php in core/modules/system/tests/modules/container_rebuild_test/src/ContainerRebuildTestServiceProvider.php
CoreServiceProvider.php in core/lib/Drupal/Core/CoreServiceProvider.php
DrupalKernel.php in core/lib/Drupal/Core/DrupalKernel.php
ErrorServiceTestServiceProvider.php in core/modules/system/tests/modules/error_service_test/src/ErrorServiceTestServiceProvider.php
FileServiceProvider.php in core/modules/file/src/FileServiceProvider.php
InstallerServiceProvider.php in core/lib/Drupal/Core/Installer/InstallerServiceProvider.php
JsonapiServiceProvider.php in core/modules/jsonapi/src/JsonapiServiceProvider.php
ModifyServiceDefinitionsPass.php in core/lib/Drupal/Core/DependencyInjection/Compiler/ModifyServiceDefinitionsPass.php
ServiceProviderTestServiceProvider.php in core/modules/system/tests/modules/service_provider_test/src/ServiceProviderTestServiceProvider.php
UpdateServiceProvider.php in core/lib/Drupal/Core/Update/UpdateServiceProvider.php

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