Capture allows the usage of curly braces

[Bellangelo]

In this PR we tried to bypass the issue that Jekyll does not support variables in the front-matter. What we did instead was to break the syntax, once more: https://github.com/OAI/OpenAPI-Specification/actions/runs/9163554322/job/25192911220.

The documentation even proposes the syntax but i missed it originally ( face-palm ): https://jekyllrb.com/docs/includes/#passing-parameter-variables-to-includes

You can check the rendered results here: https://bellangelo.github.io/OpenAPI-Specification/registry/alternative-schema/xmlSchema.html

[handrews]

Thanks for the explanation - Jekyll always makes my head hurt, and its just as much on me for missing these things while looking over the changes. But this is a good low-impact page to experiment with!