There's a merged pull request on the void-packages repository

pandoc: add pandoc-crossref filter, move filters to subpkgs
https://github.com/void-linux/void-packages/pull/35658

Description:
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[`pandoc-crossref`](https://github.com/lierdakil/pandoc-crossref) is a filter for pandoc that adds support for numbering figures, equations, tables and cross-references to them in documents. I think a number of pandoc users may find this a useful addition.

Included in the pandoc package for faster compilation, similar to pandoc-sidenote, but now both have been moved to their own subpackages.

#### Testing the changes
- I tested the changes in this PR: **YES**

#### New package
- This new package conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements): **YES**

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