is responsible for handling references to issues, such as
`gitlab-org/gitlab#123` and `https://gitlab.com/gitlab-org/gitlab/-/issues/200048`.
All reference filters are instances of [`HTML::Pipeline::Filter`](https://www.rubydoc.info/github/jch/html-pipeline/v1.11.0/HTML/Pipeline/Filter),
All reference filters are instances of [`HTML::Pipeline::Filter`](https://www.rubydoc.info/github/jch/html-pipeline/HTML/Pipeline/Filter),
and inherit (often indirectly) from [`Banzai::Filter::ReferenceFilter`](https://gitlab.com/gitlab-org/gitlab/blob/master/lib/banzai/filter/reference_filter.rb).
`HTML::Pipeline::Filter` has a simple interface consisting of `#call`, a void