Update `cmark-gfm` and `commonmarker` gems due to vulnerability

In DOS via issue preview and markdown preview (#361982 - closed) we learned that cmark-gfm (as well as commonmarker because it wraps cmark-gfm) have a vulnerability in the autolink extension.

A patch has been sent to GitHub through their Security Policy. Until that is fixed, a workaround MR has been applied.

Once it is fixed upstream, we need to update the gems and remove the PathologicalMarkdownFilter added in the MR

Instructions to re-create the problem in cmark-gfm are outlined in #361982 (comment 974654562)

Submitted patch: 0001-Fix-pathological-case-in-autolink-extension.patch