tools: strip comments from lint-md rollup output

Refs: #41081 (comment)

PR-URL: #41092
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Tobias Nießen <[email protected]>
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Tierney Cyren <[email protected]>

Author: Trott