Core/Misc: fixed several warnings that have been exposed by the new warnings

src/server/game/Spells/SpellMgr.cpp

@@ -1500,7 +1500,7 @@ void SpellMgr::LoadSpellGroupStackRules()
                     if (!spellInfo->Effects[i].IsAura())
                         continue;
 
-                    int32 auraName = static_cast<int32>(spellInfo->Effects[i].ApplyAuraName);
+                    uint32 auraName = spellInfo->Effects[i].ApplyAuraName;
                     for (std::vector<uint32> const& subGroup : SubGroups)
                     {
                         if (std::find(subGroup.begin(), subGroup.end(), auraName) != subGroup.end())