Resolve "Source Entry Reference Fields + /free-trial l10n update"

Step 1: What is changing in this MR?

Production	Review app
https://about.gitlab.com/free-trial/	https://3706-source-entry-reference-fields-free-trial-l10n-update.about.gitlab-review.app/free-trial/
https://about.gitlab.com/fr-fr/free-trial/	https://3706-source-entry-reference-fields-free-trial-l10n-update.about.gitlab-review.app/fr-fr/free-trial/
https://about.gitlab.com/de-de/free-trial/	https://3706-source-entry-reference-fields-free-trial-l10n-update.about.gitlab-review.app/de-de/free-trial/
https://about.gitlab.com/ja-jp/free-trial/	https://3706-source-entry-reference-fields-free-trial-l10n-update.about.gitlab-review.app/ja-jp/free-trial/

Step 2: Ensure that your changes comply with the following, where applicable:

• I, the Assignee, have run Axe tools on any updated pages, and fixed the relevant accessibility issues.
• These changes work on both Safari, Chrome, and Firefox.
• These changes have been reviewed for Visual Quality Assurance and Functional Quality Assurance on Mobile, Desktop, and Tablet.
• These changes work with our Google Analytics and SEO tools.
• These changes have been documented as expected.

Build Variables:

• Use Contentful Preview API

Closes #3706 (closed)