As book is now contributed module we need to make changes in our tests as it starts failing for current and previous minor if I put in the require-dev section
Laminas/laminas-feed
ExtensionManagerInterface → is also deprecated which is implemented in ZfExtensionManagerSfContainer and SyndicationParser (Needs extra effort here)
DataProviders should be static
Fix all deprecated phpunit methods like returnValue(), returnValueMap(), returnCallback() and many more.
Proposed resolution
Add drupal/book-book: "^1" in the require-dev section of composer json.