Run mupip backup and routine consistency check in parallel

Currently, the ovbackup script calls rsync --dry-run after mupip backup completes to check if the routines have changed while the database files were being backed up. The rsync call can actually occur as soon as mupip backup starts, because GT.M backups are consistent to the point in time when a backup is started, not when the backup completes.

Doing the rsync call while mupip backup is still running shortens the window of time where the routines must stay static. If the database is large, mupip backup can take hours, so there is a big difference.