Marked tab bug has been fixed for a while, so we should pull (if needed) and rip out the hack

[dead-claudia]

Link: markedjs/marked#3440

Simplified code: markedjs/marked#2134 (comment)

Relevant script as linked in the relevant Marked issue: https://github.com/MithrilJS/mithril.js/blob/64ae328f6213a83ae54dd42692b8b9a9ace52050/scripts/_lint-docs/process-file.js