fix: Prevent internal router from handling external links

[robvanbakel]

closes #2086

What is the purpose of this pull request?

• [ ] New Icon
• [x] Bug fix
• [ ] New Feature
• [ ] Documentation update
• [ ] Other:

Description

Links in badges that open externally would also be picked up by the Vue Router, resulting in a 404-page.

Detection for external links is added in the Badge component, simultaneously adding the appropriate anchor tag attributes, as well as preventing the Vue Router from navigating.

Before Submitting

• [x] I've read the Contribution Guidelines.
• [x] I've checked if there was an existing PR that solves the same issue.