To support testing and feature flagging of resumable index builds, the work in this ticket should include:

• * add startup server parameter
• add server status field for feature support to storage engine section
  • depends on:
    • support for EMRC
    • support for persistence
    • FCV
    • startup server parameter value.
• initial tasks should include noPassthrough
• add js test helper to index_build.js to query support for resumable index build in tests.
• add internal function to IndexBuildsCoordinator to check for support.