IndexBuildsManager::setUpIndexBuild must be split out of IndexBuilsdCooridnator::_runIndexBuild, and called elsewhere on a different thread (see
SERVER-39369). Refactor the code to facilitate this, since the refactor is a significant change.
- is caused by
SERVER-37643 add createIndexes command logic to the index build interface
- is depended on by
SERVER-39369 Filter index builds requests in the coordinator, register the builds on the Coordinator and set them up in the persisted catalog before changing threads