[server] add a looping task to free unused cnxsets capture by dead pyro
When a pyro client disconnects, we're not necessarily notified so they
can hang on to their session/cnxset forever. Don't let them do that.
The hacky looping task is only installed when pyro is enabled. This optional
activation save this very hacky patch from being rejected.
closes #2825380
Latest changes
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* table of `all latest changes`_
Links below is providing useful RQL query example.
.. _all latest changes: view?rql=Any+M%2CX+WHERE+X+modification_date+M+ORDERBY+M+DESC+LIMIT+30