fix: rounding error in GNS

Author: Maikol

packages/contracts/contracts/discovery/GNS.sol

@@ -740,10 +740,13 @@ abstract contract GNS is GNSV3Storage, GraphUpgradeable, IGNS, Multicall {
             return _tokens;
         }
 
-        // Tax on the total bonding curve funds
-        uint256 taxOnOriginal = _tokens.mul(_curationTaxPercentage).div(MAX_PPM);
         // Total after the tax
-        uint256 totalWithoutOwnerTax = _tokens.sub(taxOnOriginal);
+        uint256 totalWithoutOwnerTax = uint256(MAX_PPM)
+            .sub(_curationTaxPercentage)
+            .mul(_tokens)
+            .div(MAX_PPM);
+        // Tax on the total bonding curve funds
+        uint256 taxOnOriginal = _tokens.sub(totalWithoutOwnerTax);
         // The portion of tax that the owner will pay
         uint256 ownerTax = taxOnOriginal.mul(ownerTaxPercentage).div(MAX_PPM);