Fix S(a,b) ZAID bugs in NNDC data when converting
Fix S(a,b) ZAID bugs in NNDC data when converting

johnnyliu27/openmc,liangjg/openmc,mit-crpg/openmc,amandalund/openmc,shikhar413/openmc,shikhar413/openmc,walshjon/openmc,paulromano/openmc,mit-crpg/openmc,wbinventor/openmc,liangjg/openmc,walshjon/openmc,smharper/openmc,paulromano/openmc,johnnyliu27/openmc,amandalund/openmc,johnnyliu27/openmc,paulromano/openmc,liangjg/openmc,liangjg/openmc,shikhar413/openmc,shikhar413/openmc,wbinventor/openmc,amandalund/openmc,amandalund/openmc,mit-crpg/openmc,bhermanmit/openmc,bhermanmit/openmc,wbinventor/openmc,smharper/openmc,mit-crpg/openmc,smharper/openmc,walshjon/openmc,johnnyliu27/openmc,wbinventor/openmc,paulromano/openmc,smharper/openmc,walshjon/openmc