fix: removing owner check from make swap

- removed the owner check because although the owner needs to be msg.sender, we should not check for view functions since once third party entity could create a swap for someone

contracts/echidna/TestSwapFactory.sol

@@ -37,7 +37,6 @@ contract TestFactory is SwapFactory {
             make_asset_array(addr, amountOrId)
         );
 
-        assert(owner != address(0));
         assert(swap.expiry > block.timestamp);
         assert(swap.biding.length > 0);
         assert(swap.asking.length > 0);