restore trustedForwarders as an OZ override

contracts/lib/metatx/ERC2771Context.sol

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { ERC2771Context } from "@openzeppelin/contracts/metatx/ERC2771Context.sol";
+
+abstract contract ERC2771 is ERC2771Context(address(0)) {
+    mapping(address => bool) public trustedForwarders;
+    
+    function isTrustedForwarder(address forwarder) public view override returns (bool) {
+      return trustedForwarders[forwarder];
+    }
+
+}