Placeholder: Support null values in StyxObjectStore.compute

[mikkokar]

A TODO in HealthCheckMonitoringService.kt:

    // The ifPresent is not ideal, but compute() does not allow the computation to return null. So we can't preserve
     // a state where the object does not exist using compute alone. But even with ifPresent, as we are open to
     // the object disappearing between the ifPresent and the compute, which would again lead to the compute creating
     // a new object when we don't want it to. But at least this will happen much less frequently.
     db.get(name).ifPresent {

[bestokes]

Fixed in PR #629