tools: update markdown linter for Windows line endings

Update the markdown linter to work with Windows line endings.
Previously, Windows line endings would break the trailing-spaces plugin.

PR-URL: https://github.com/nodejs/node/pull/27756


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>