b27d8c5d0a
Fixes https://github.com/NixOS/nixpkgs/issues/27996. Updates instructions for generating hashes passwords for use in a Mosquitto password file. Using `mosquitto_passwd` to generate these hashes is a little less convenient, but the results are more likely to be compatible with the mosquitto daemon. As far as I can tell, the hashes generated with `mkpassd` did not work as intended. But this may have been hidden by another bug: https://github.com/NixOS/nixpkgs/issues/27130.