Fix a bug in extra JS rendering

[grozdanowski]

Change description

Bug was that if no extra JS is defined in site config, it would render weird {} at top and bottom of page. This hopefully fixes it.

Type of change

• [x] Bug fix (fixes an issue)
• [ ] New feature (adds functionality)

Related issues

Fix [#1]()

Checklists

Development

• [ ] Lint rules pass locally
• [ ] Application changes have been tested thoroughly
• [ ] Automated tests covering modified code pass

Security

• [ ] Security impact of change has been considered
• [ ] Code follows company security practices and guidelines

Code review

• [ ] Pull request has a descriptive title and context useful to a reviewer. Screenshots or screencasts are attached as necessary
• [ ] "Ready for review" label attached and reviewers assigned
• [ ] Changes have been reviewed by at least one other contributor
• [ ] Pull request linked to task tracker where applicable