Preserve CRLF newlines in artifacts
In certain edge cases, the newlines may be relevant, e.g. in https://sequoia-pgp.gitlab.io/openpgp-interoperability-test-suite/results.html#Problematic_Cleartext_Signature_Sign-Verify_roundtrip, where the artifact generated by OpenPGP.js can't be validated by rpgp due to the newlines, which can't be reproduced by the generated command since the newlines are normalized by HTML when unescaped. This patch escapes them to preserve the original newlines.