Iterations GFM syntax does not work for format

Summary

Markdown like [Text](*iteration:"iteration name") links to nothing instead of the existing iteration.

Sample text	Hover on correctly formatted link	Hover on incorrectly formatted link

In the same text above, the first two options work correctly, the latter two are broken.

What is the expected correct behavior?

There should be a link like <a href="link/to/iteration">Text</a>

Possible fixes

Relevant location: https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/utils/sanitize_node_link.rb#L48

Addressable::URI.parse("*iteration:14") will raise an error, as : is not part of a valid url. One option may be to rescue when using Gitlab reference formats. However, this code is not part of the GFM pipeline, so we wouldn't necessarily know which filters were applicable.

An alternate option may be to choose a different reference prefix for iterations.