Use hardhat-exposed to reduce the need for mocks (#3666)

Co-authored-by: Francisco <fg@frang.io>

contracts/mocks/proxy/ClashingImplementation.sol

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.0;
+
+/**
+ * @dev Implementation contract with an admin() function made to clash with
+ * @dev TransparentUpgradeableProxy's to test correct functioning of the
+ * @dev Transparent Proxy feature.
+ */
+contract ClashingImplementation {
+    function admin() external pure returns (address) {
+        return 0x0000000000000000000000000000000011111142;
+    }
+
+    function delegatedFunction() external pure returns (bool) {
+        return true;
+    }
+}