Create separate background worker to analyze partition sets

[keithf4]

PostgreSQL still does not have a means to automatically analyze a partition set from the parent level. Distinct statistics are gathered when this is done for optimized partition querying.

Currently the maintenance procedure has an option to analyze the partition sets as part of that maintenance, but this was disabled being on by default due to causing long maintenance run times which in turn cause locking issues.

Create a separate background worker that is explicitly for running analyze at the parent level. Can use the existing run_analyze() function