Swayidle will likely end up dropping logind support, and they themselves
describe it as unstable. For this reason, move to the suggested
alternative: systemd-lock-handler, and just have swayidle run the
command to trigger the logind session lock event, picked up by
systemd-lock-handler.
See <https://github.com/swaywm/swayidle/issues/117> for reference.
