6 files declare their use of CacheableResponseTrait

CacheableResourceResponse.php in core/modules/jsonapi/src/CacheableResourceResponse.php
CacheableSecuredRedirectResponse.php in core/lib/Drupal/Core/Routing/CacheableSecuredRedirectResponse.php
CacheableTestResponse.php in core/modules/system/tests/modules/early_rendering_controller_test/src/CacheableTestResponse.php
HtmlResponse.php in core/lib/Drupal/Core/Render/HtmlResponse.php
ResourceResponse.php in core/modules/rest/src/ResourceResponse.php
SectionComponentBuildRenderArrayEvent.php in core/modules/layout_builder/src/Event/SectionComponentBuildRenderArrayEvent.php

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