feat: Move approval from transferProxy to Augustus

Author: miguelmtzinf

src/contracts/extensions/paraswap-adapters/BaseParaSwapBuyAdapter.sol

@@ -75,8 +75,7 @@ abstract contract BaseParaSwapBuyAdapter is BaseParaSwapAdapter {
     require(balanceBeforeAssetFrom >= maxAmountToSwap, 'INSUFFICIENT_BALANCE_BEFORE_SWAP');
     uint256 balanceBeforeAssetTo = assetToSwapTo.balanceOf(address(this));
 
-    address tokenTransferProxy = augustus.getTokenTransferProxy();
-    assetToSwapFrom.safeApprove(tokenTransferProxy, maxAmountToSwap);
+    assetToSwapFrom.safeApprove(address(augustus), maxAmountToSwap);
 
     if (toAmountOffset != 0) {
       // Ensure 256 bit (32 bytes) toAmountOffset value is within bounds of the
@@ -102,7 +101,7 @@ abstract contract BaseParaSwapBuyAdapter is BaseParaSwapAdapter {
     }
 
     // Reset allowance
-    assetToSwapFrom.safeApprove(tokenTransferProxy, 0);
+    assetToSwapFrom.safeApprove(address(augustus), 0);
 
     uint256 balanceAfterAssetFrom = assetToSwapFrom.balanceOf(address(this));
     amountSold = balanceBeforeAssetFrom - balanceAfterAssetFrom;

src/contracts/extensions/paraswap-adapters/BaseParaSwapSellAdapter.sol

@@ -72,9 +72,7 @@ abstract contract BaseParaSwapSellAdapter is BaseParaSwapAdapter {
     require(balanceBeforeAssetFrom >= amountToSwap, 'INSUFFICIENT_BALANCE_BEFORE_SWAP');
     uint256 balanceBeforeAssetTo = assetToSwapTo.balanceOf(address(this));
 
-    address tokenTransferProxy = augustus.getTokenTransferProxy();
-    assetToSwapFrom.safeApprove(tokenTransferProxy, 0);
-    assetToSwapFrom.safeApprove(tokenTransferProxy, amountToSwap);
+    assetToSwapFrom.safeApprove(address(augustus), amountToSwap);
 
     if (fromAmountOffset != 0) {
       // Ensure 256 bit (32 bytes) fromAmount value is within bounds of the
@@ -99,6 +97,9 @@ abstract contract BaseParaSwapSellAdapter is BaseParaSwapAdapter {
       }
     }
 
+    // Reset allowance
+    assetToSwapFrom.safeApprove(address(augustus), 0);
+
     require(
       assetToSwapFrom.balanceOf(address(this)) == balanceBeforeAssetFrom - amountToSwap,
       'WRONG_BALANCE_AFTER_SWAP'