Adding Google Book Actions to books pages

Book actions make Google Search an entry point for discovering books and authors, enabling Search users to quickly buy the books that they find directly from Search results. As a provider of e-books, you can provide a feed of data to Google using the structured data schema below.

### Proposal & Constraints

Its is a limited access feature and needs to be implemented according to these guidelines https://developers.google.com/search/docs/data-types/book#guidelines

We’ll want to submit our url to https://docs.google.com/forms/d/e/1FAIpQLSciint0VNW9RYBEdX4VyZTfkQZIS7L695yf1J9ySA_8yfa9ww/viewform

We can test here:
https://search.google.com/structured-data/testing-tool

### Stakeholders

@mekarpeles

The issue names the books pages as the entry point and links to Google's Book Actions guidelines and structured-data testing tool. Start by locating how those pages are rendered, then compare the available book data with the required markup. Done means the pages expose valid Google Book Actions data and the submission can be made through the linked form.

Written by the indexing model from the issue text.