Fix nav default order

[dogfuntom]

Description

Nav plugin was ignoring the default order for the children option passed during its import/installation.

Check List

• Have you read the
  CODE OF CONDUCT
• Have you read the document
  CONTRIBUTING
  • One pull request per feature. If you want to do more than one thing,
    send multiple pull request.
  • Write tests.
  • Run deno fmt to fix the code format before commit.
  • Document any change in the CHANGELOG.md.

[dogfuntom]

However, the nav.tests now fail because of some kind of newline (dis)appearance between </html> and ',.

[oscarotero]

Thank you!