Fix error in property setter for num_flushes
Fix error in property setter for num_flushes

smharper/openmc,shikhar413/openmc,johnnyliu27/openmc,kellyrowland/openmc,johnnyliu27/openmc,walshjon/openmc,amandalund/openmc,bhermanmit/openmc,paulromano/openmc,mit-crpg/openmc,mit-crpg/openmc,smharper/openmc,wbinventor/openmc,johnnyliu27/openmc,smharper/openmc,amandalund/openmc,samuelshaner/openmc,paulromano/openmc,amandalund/openmc,mjlong/openmc,walshjon/openmc,samuelshaner/openmc,liangjg/openmc,wbinventor/openmc,wbinventor/openmc,mit-crpg/openmc,smharper/openmc,samuelshaner/openmc,kellyrowland/openmc,liangjg/openmc,liangjg/openmc,shikhar413/openmc,liangjg/openmc,mjlong/openmc,shikhar413/openmc,walshjon/openmc,lilulu/openmc,mit-crpg/openmc,lilulu/openmc,johnnyliu27/openmc,shikhar413/openmc,walshjon/openmc,paulromano/openmc,wbinventor/openmc,lilulu/openmc,paulromano/openmc,amandalund/openmc,samuelshaner/openmc,bhermanmit/openmc