Support conventional-changelog-config-spec in nx release

[m3Lith]

Currently, release command seems to be heavily tied to GitHub repository URLs.

For example, when geenrating changelog in a GitLab repo, no URLs are added.

Supporting this spec would allow customizing URLs (for commits, compares, issues), among other things, which now require writing a full custom renderer.

https://github.com/conventional-changelog/conventional-changelog-config-spec