message: Fix a Mexican UHV Python error
diff: @@ -1693,7 +1693,7 @@ def onBuildingBuilt(city, iBuilding):
  # first Mexican goal: build three cathedrals of your state religion by 1880 AD
  elif iCiv == iMexico:
  if isPossible(iPlayer, 0):
  - iStateReligion = pPlayer.getStateReligion()
  + iStateReligion = player(iPlayer).getStateReligion()
  if iStateReligion >= 0:
  iStateReligionCathedral = iCathedral + 4 * iStateReligion
  if iBuilding == iStateReligionCathedral:
  