When a server goes into maintenance, the current state is set to
Maintenance and the previous state is left unmodified. The function which
checks for state changes uses the current and previous values and simply
compares them. Since servers in maintenance mode aren't monitored, the
function always returned true when servers were in maintenance mode.
When the state change to or from maintenance is ignored, the state change
function works. With this fix, users can safely put servers into
maintenance without having to worry about the scripts being executed. This
also allows the scripts themselves to put servers into maintenance.
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