Decrease query.low-memory-killer.delay to 30s

[raunaqmorarka]

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# General
* Reduce delay in killing of queries when the cluster runs out of memory ({issue}`issuenumber`)

[sopel39]

Could you check how often coordinator updates status of worker memory pools? I think it's few secs at most

[raunaqmorarka]

Could you check how often coordinator updates status of worker memory pools? I think it's few secs at most

SqlQueryManager will trigger async refreshes when it finds worker memory pool info to be more than 1 second stale and it's running this loop every second.

[findepi]

thanks