Fix UnoCSS plugin's JSDoc

[quadratz]

Description

Corrected @default values in UnoCSS plugin's JSDoc.

Related Issues

N/A

Check List

• [x] Have you read the CODE OF CONDUCT
• [x] Have you read the document CONTRIBUTING
  • [x] One pull request per feature. If you want to do more than one thing, send multiple pull request.
  • [ ] ~Write tests.~
  • [x] Run deno fmt to fix the code format before commit.
  • [ ] ~Document any change in the CHANGELOG.md.~ (too minor to have its own line)

[oscarotero]

Thank you!