Migrate utils-structs tests to ethersjs (#4748)

Co-authored-by: Hadrien Croubois <hadrien.croubois@gmail.com>
Co-authored-by: ernestognw <ernestognw@gmail.com>

test/helpers/random.js

@@ -0,0 +1,14 @@
+const { ethers } = require('hardhat');
+
+const randomArray = (generator, arrayLength = 3) => Array(arrayLength).fill().map(generator);
+
+const generators = {
+  address: () => ethers.Wallet.createRandom().address,
+  bytes32: () => ethers.hexlify(ethers.randomBytes(32)),
+  uint256: () => ethers.toBigInt(ethers.randomBytes(32)),
+};
+
+module.exports = {
+  randomArray,
+  generators,
+};