- Remove a unused dependency. This dependency was added to handle YAML
'frontmatter' meta, parsing them and converting them to a table or
details in the resulting HTML. As can be read in the issue that reported
the behavior of YAML frontmatter being rendered literally,
https://github.com/go-gitea/gitea/issues/5377.
- It's an unused dependency as the codebase since then moved on to do this YAML
parsing and rendering on their own, this was implemented in
812cfd0ad9.
- Adds unit tests that was related to this functionality, to proof the
codebase already handles this and to prevent regressions.