Watches for changes to the set of mount entries and mount points in the system.
Connect to the [signal@GioUnix.MountMonitor:GUnixMountMonitor:mounts-changed] signal to be notified of changes to the [
struct@GioUnix.MountEntry] list.
Connect to the [signal@GioUnix.MountMonitor:GUnixMountMonitor:mountpoints-changed] signal to be notified of changes to the [
struct@GioUnix.MountPoint] list.