Update characters.en.mdx - Fix attribute name typo

[avishj]

Summary

Fixes the typo's in the attribute docs for characters.

Related Issues

Fixes #836

Checklist

• [x] This pull request has a meaningful title and description.
• [x] I have read and followed the Contributing guidelines.
• [x] My code follows the conventions and coding style of this project.
• [x] All tests pass and I have added tests for my changes
• [x] I have updated necessary documentation

Screenshots (if applicable)

Additional information