Support for more schema.org types

The linter issues a warning if some schema.org types can't be found. It should "allow" more types:


(See https://developers.google.com/search/docs/guides/about-amp.)

See also #397.

Start by locating the linter logic that warns when schema.org types cannot be found, then compare its allowlist with the types shown in the linked image and AMP documentation. Use #397 for related context. Done means the additional schema.org types are accepted without warnings and existing behavior remains covered by the relevant tests.

Written by the indexing model from the issue text.