ITS#9598 Do not track olcIncomingConnections in lloadd/test007

Some values we export in cn=monitor are not managed in a single place, instead, a task exists that gathers a snapshot of the lloadd state and stores it for monitor consumption. This exposes a race between the test reading it out and lloadd updating this cached copy. While we still have to rely on a shell, rather than being intelligent about whether or not we should emit a readout into search.out or wait and try again (which is what test004-monitor does), just filter this attribute out.