Live preview for contentful

Reviewer Checklist:

• I, the Assignee, have run Axe tools on any updated pages, and fixed the relevant accessibility issues
• These changes meet a specific OKR or item in our Quarterly Plan.
• These changes work on both Safari and Chrome.
• These changes have been reviewed for Visual Quality Assurance and Functional Quality Assurance on Mobile, Desktop, and Tablet.
• These changes comply with SEO best practices.
• Changes with links meet the data attributes requirement for Google Analytics tracking.
• Changes with interactive elements that aren't links (video, drop-down menu, form, etc.) sends a dataLayer event for Google Analytics tracking.
• These changes have been documented as expected.

Build Variables:

• Use Contentful Preview API