Core/Spells: improve random radius calculation by reducing the chance of hitting the center the closer we get

src/server/game/Spells/SpellInfo.cpp

@@ -674,7 +674,7 @@ float SpellEffectInfo::CalcRadius(WorldObject* caster /*= nullptr*/, SpellTarget
     if (target.GetTarget() == TARGET_DEST_CASTER_RANDOM ||
         target.GetTarget() == TARGET_DEST_TARGET_RANDOM ||
         target.GetTarget() == TARGET_DEST_DEST_RANDOM)
-        radius += (entry->RadiusMax - radius) * rand_norm();
+        radius += (entry->RadiusMax - radius) * std::sqrt(rand_norm());
     else if (radius == 0.0f)
         radius = entry->RadiusMax;