Fix structured data parsing from links choking on bad data (#17403)

* Fix structured data parsing from links choking on bad data

- Fix og:url meta tag being prioritized over canonical link tag
- Fix structured data parsing choking on commented-out CDATA declarations
- Fix HTML entities in title, description, provider_name, author_name
- Change structured data parsing to attempt every JSON-LD script tag

* Remove unnecessary slash escapes from CDATA regex pattern