Add pet battle events for mop (#5938)

Author: mopstats

WeakAuras/WeakAuras.lua

@@ -1860,6 +1860,11 @@ if WeakAuras.IsCataOrMists() then
   loadFrame:RegisterEvent("UPDATE_VEHICLE_ACTIONBAR")
   loadFrame:RegisterEvent("UPDATE_OVERRIDE_ACTIONBAR");
 end
+
+if WeakAuras.IsMists() then
+  loadFrame:RegisterEvent("PET_BATTLE_OPENING_START");
+  loadFrame:RegisterEvent("PET_BATTLE_CLOSE");
+end
 loadFrame:RegisterEvent("GROUP_ROSTER_UPDATE");
 loadFrame:RegisterEvent("ZONE_CHANGED");
 loadFrame:RegisterEvent("ZONE_CHANGED_INDOORS");