* fix(threadpool): MCOL-5565 queries stuck in FairThreadScheduler. (#3100)
Meta Primitive Jobs, .e.g ADD_JOINER, LAST_JOINER stuck
in Fair scheduler without out-of-band scheduler. Add OOB
scheduler back to remedy the issue.
* fix(messageqcpp): MCOL-5636 same node communication crashes transmiting PP errors to EM b/c error messaging leveraged socket that was a nullptr. (#3106)
* fix(threadpool): MCOL-5645 errenous threadpool Job ctor implictly sets socket shared_ptr to nullptr causing sigabrt when threadpool returns an error (#3125)
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Co-authored-by: drrtuy <roman.nozdrin@mariadb.com>
DBRM connections are reused so that we don't have a huge amount of
TIME_WAIT sockets when there are large amounts of DML. Also applied to
i_s.columnstore_files
