Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2600538 by rakesh.gectcr, anil280988, justAChris, jhodgdon: Incorrect @file description in core/ classes - wrong namespace or class name

Issue #2552013 by Wim Leers: Follow-up for #2481453: ensure the 'url.query_args': MainContentViewSubscriber::WRAPPER_FORMAT cache context is set

Issue #2463009 by Wim Leers: Introduce CacheableResponseInterface: consolidate ways of setting X-Drupal-Cache-Tags/Contexts headers