If you’re doing this not on Meta, you probably need whatever TC Meta uses for it. (idk what/where that would be either)
If you are doing it on meta, it should work.
Random example #theme-component topic
[wrap=theme-install-button repoUrl="https://github.com/discourse/discourse-top-contributors-sidebar" repoName="Discourse Top Contributors Sidebar"]
Install this theme component
[/wrap]
Parsed:
Install this theme component