9 files declare their use of EntityDefinitionUpdateManagerInterface

ContentEntityNonRevisionableFieldTest.php in core/tests/Drupal/KernelTests/Core/Entity/ContentEntityNonRevisionableFieldTest.php
ContentModerationStateTest.php in core/modules/content_moderation/tests/src/Kernel/ContentModerationStateTest.php
DefaultTableMappingIntegrationTest.php in core/tests/Drupal/KernelTests/Core/Entity/DefaultTableMappingIntegrationTest.php
EntityDefinitionTestTrait.php in core/modules/system/tests/src/Functional/Entity/Traits/EntityDefinitionTestTrait.php
EntitySchemaSubscriber.php in core/modules/workspaces/src/EventSubscriber/EntitySchemaSubscriber.php
EntitySchemaSubscriber.php in core/modules/system/tests/modules/entity_test_update/src/EventSubscriber/EntitySchemaSubscriber.php
EntitySchemaTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntitySchemaTest.php
EntityTestResourceTestBase.php in core/modules/system/tests/modules/entity_test/tests/src/Functional/Rest/EntityTestResourceTestBase.php
SqlContentEntityStorageSchemaColumnTest.php in core/modules/field/tests/src/Kernel/Entity/Update/SqlContentEntityStorageSchemaColumnTest.php

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