LJ-700: Fix Special-purpose only vendors not correctly encoded in TC string

[eastandwestwind]

Closes https://ethyca.atlassian.net/browse/LJ-700

Description Of Changes

Fix Special-purpose only vendors not correctly encoded in TC string

Code Changes

• Update tcf encoding logic to consider special-purpose only vendors
• Adds specific test for this scenario

Steps to Confirm

1. Login to the Fides Admin UI
2. Navigate to the Vendors configuration
3. Enable a special-purpose only vendor (e.g. SeenThis) in the vendor list
4. Save the configuration
5. Ensure you have a system with data use added in Admin-UI
6. Enable the TCF experience
7. Visit http://localhost:3001/fides-js-demo.html?geolocation=fr-idf&fides_locale=en
8. Confirm that SeenThis vendor is listed under Purposes -> Legitimate Interest -> Special purposes section

9. Make a consent choice (or just x out of the banner), the action doesn't matter
10. Inspect the generated TC string, either through the console (__tcfapi("getTCData", 2, console.log)), using the IAB chrome extension to inspect, or otherwise, to see that SeenThis is enabled (vendor 415)

Pre-Merge Checklist

• Issue requirements met
• All CI pipelines succeeded
• CHANGELOG.md updated
  • Add a db-migration This indicates that a change includes a database migration label to the entry if your change includes a DB migration
  • Add a high-risk This issue suggests changes that have a high-probability of breaking existing code label to the entry if your change includes a high-risk change (i.e. potential for performance impact or unexpected regression) that should be flagged
  • Updates unreleased work already in Changelog, no new entry necessary
• Followup issues:
  • Followup issues created
  • No followup issues
• Database migrations:
  • Ensure that your downrev is up to date with the latest revision on main
  • Ensure that your downgrade() migration is correct and works
    • If a downgrade migration is not possible for this change, please call this out in the PR description!
  • No migrations
• Documentation:
  • Documentation complete, PR opened in fidesdocs
  • Documentation issue created in fidesdocs
  • If there are any new client scopes created as part of the pull request, remember to update public-facing documentation that references our scope registry
  • No documentation updates required

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[gilluminate]

Thanks for the update!

[cypress]

fides    Run #12868

Run Properties:   Passed #12868  •  3d3262d53a: LJ-700: Fix Special-purpose only vendors not correctly encoded in TC string (#60...

Project	fides
Branch Review	main
Run status	Passed #12868
Run duration	00m 54s
Commit	3d3262d53a: LJ-700: Fix Special-purpose only vendors not correctly encoded in TC string (#60...
Committer	Catherine Smith
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