🐛 fix(article-navigation): adjust spacing for RTL

[welpo]

Summary

This PR addresses an issue where right-to-left (RTL) languages were not displaying proper spacing and direction for navigation arrows in the article-navigation at the end of posts.

Related issue

Fixes #274.

Changes

Screenshots

Before:

After:

Type of change

• [X] Bug fix (fixes an issue without altering functionality)
• [ ] New feature (adds non-breaking functionality)
• [ ] Breaking change (alters existing functionality)
• [ ] UI/UX improvement (enhances user interface without altering functionality)
• [ ] Refactor (improves code quality without altering functionality)
• [ ] Documentation update
• [ ] Other (please describe below)

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Checklist

• [ ] I have verified the accessibility of my changes
• [X] I have tested all possible scenarios for this change
• [ ] I have updated theme.toml with a sane default for the feature
• [ ] I have made corresponding changes to the documentation:
  • [ ] Updated config.toml comments
  • [ ] Updated theme.toml comments
  • [ ] Updated "Mastering tabi" post in English
  • [ ] (Optional) Updated "Mastering tabi" post in Spanish
  • [ ] (Optional) Updated "Mastering tabi" post in Catalan