Temporary workaround for #777 while we investigate googlesource.com
test/30-audio: Install recommended deps for pulseaudio

pulseaudio 5.0 on jessie (and probably sid) requires dbus-daemon to
be running in its default configuration. However,
`install --minimal pulseaudio` does not pull in dbus.

Removing --minimal ensures dbus is installed, as it would be in
most real cases.