Only reduce tallies if n_procs > 1
Only reduce tallies if n_procs > 1

shikhar413/openmc,paulromano/openmc,amandalund/openmc,paulromano/openmc,mit-crpg/openmc,shikhar413/openmc,mit-crpg/openmc,paulromano/openmc,mit-crpg/openmc,shikhar413/openmc,walshjon/openmc,walshjon/openmc,amandalund/openmc,shikhar413/openmc,walshjon/openmc,mit-crpg/openmc,paulromano/openmc,amandalund/openmc,amandalund/openmc,walshjon/openmc