Restrict source probability column to pSource on run summary page
Currently the O4 public event display https://gracedb.ligo.org/superevents/public/#O4 includes 'HasMassGap' as a source probability if nonzero. However, there is no longer a 'MassGap' source class or category, and 'HasMassGap' is a possible property of a source if the source has one or more BH components. The calculation for HasMassGap is quite different from the previous O3 p(MG) calculation, and if HasMassGap is >0 then the total probability will add up to more than 100% including the current source types/classes (BNS, NSBH, BBH, Terr), since events in the NSBH and BBH classes can have MassGap components.
Request is to show only the pBNS, pNSBH, pBBH and pTerr probabilities, which together now add up to 100%, in the 'possible source (probability)' column.