Update data-tests.md

[ialdg]

Hi.
This modification proposal adds for the "accepted_values" test, a feature that it shares with the Unique test, not present in the text. Regards.
IL.

What are you changing in this pull request and why?

Checklist

• Review the Content style guide so my content adheres to these guidelines.
• For docs versioning, review how to version a whole page and version a block of content.
• Add a checklist item for anything that needs to happen before this PR is merged, such as "needs technical review" or "change base branch."

Adding or removing pages (delete if not applicable):

• Add/remove page in website/sidebars.js
• Provide a unique filename for new pages
• Add an entry for deleted pages in website/vercel.json
• Run link testing locally with npm run build to update the links that point to deleted pages

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
docs-getdbt-com	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jul 25, 2024 4:22pm

[matthewshaver]

Created as issue to be addressed #5892