DWH Export: Pause export process during updates

Currently the DWH Export takes hours to complete. If this process is running during the time we release an update to Clarizen, the Export will be aborted with an error and does not restart. The only solution is to not schedule an export during an update window, but since updates can take hours, this has to be manually managed by the customer. For future reference, the feature request ID is: CR-404659.