Incorrect command for dump-plugins

[nyboer]

In the section on getting a JSON of parameters for a configuration located here
The command has a typo, and doesn't really work in concert with other documentation.
The typo is that the double dash was turned into an "m" dash, so it's very hard to notice and causes much mental pain :)
It should be --dump-plugins not –dump-plugins. Since other docs are using the config file "play_vst3.json", it would be helpful to stay consistent. It also needs the -d flag for a dummy frontend. Here's an ideal version for those just getting started in this stuff on the pi:

sushi -d --dump-plugins -c ./config_files/play_vst3.json

(which assumes you are in /home/mind/ already)

Thanks!