fix: remove immutables from superchain erc20 beacon

packages/contracts-bedrock/scripts/L2Genesis.s.sol

@@ -538,21 +538,14 @@ contract L2Genesis is Deployer {
         _setImplementationCode(Predeploys.OPTIMISM_SUPERCHAIN_ERC20_FACTORY);
     }
 
-    /// @notice This predeploy is following the safety invariant #2.
+    /// @notice This predeploy is following the safety invariant #1.
+    ///         This contract has no initializer.
     function setOptimismSuperchainERC20Beacon() internal {
         address superchainERC20Impl = Predeploys.OPTIMISM_SUPERCHAIN_ERC20;
         console.log("Setting %s implementation at: %s", "OptimismSuperchainERC20", superchainERC20Impl);
         vm.etch(superchainERC20Impl, vm.getDeployedCode("OptimismSuperchainERC20.sol:OptimismSuperchainERC20"));
 
-        OptimismSuperchainERC20Beacon beacon = new OptimismSuperchainERC20Beacon(superchainERC20Impl);
-        address beaconImpl = Predeploys.predeployToCodeNamespace(Predeploys.OPTIMISM_SUPERCHAIN_ERC20_BEACON);
-
-        console.log("Setting %s implementation at: %s", "OptimismSuperchainERC20Beacon", beaconImpl);
-        vm.etch(beaconImpl, address(beacon).code);
-
-        /// Reset so its not included state dump
-        vm.etch(address(beacon), "");
-        vm.resetNonce(address(beacon));
+        _setImplementationCode(Predeploys.OPTIMISM_SUPERCHAIN_ERC20_BEACON);
     }
 
     /// @notice Sets all the preinstalls.

packages/contracts-bedrock/semver-lock.json

@@ -120,8 +120,8 @@
     "sourceCodeHash": "0xe853817da47d32b4ec5bb5392405278c82a1e9620aef377491dcb371fbbe682f"
   },
   "src/L2/OptimismSuperchainERC20Beacon.sol": {
-    "initCodeHash": "0x99ce8095b23c124850d866cbc144fee6cee05dbc6bb5d83acadfe00b90cf42c7",
-    "sourceCodeHash": "0x5e58b7c867fafa49fe39d68d83875425e9cf94f05f2835bdcdaa08fc8bc6b68e"
+    "initCodeHash": "0x23dba3ceb9e58646695c306996c9e15251ac79acc6339c1a93d10a4c79da6dab",
+    "sourceCodeHash": "0xf4379e49665823c877f5732f35068435ce06e2394fce6910a5e113d16cdc9f95"
   },
   "src/L2/OptimismSuperchainERC20Factory.sol": {
     "initCodeHash": "0x524bc58927ca60ba2fbc4b036ad00c5055758d5c5b2ebb3d75cb9b996175f2cb",

packages/contracts-bedrock/snapshots/abi/OptimismSuperchainERC20Beacon.json

@@ -1,15 +1,4 @@
 [
-  {
-    "inputs": [
-      {
-        "internalType": "address",
-        "name": "_implementation",
-        "type": "address"
-      }
-    ],
-    "stateMutability": "nonpayable",
-    "type": "constructor"
-  },
   {
     "inputs": [],
     "name": "implementation",
@@ -20,7 +9,7 @@
         "type": "address"
       }
     ],
-    "stateMutability": "view",
+    "stateMutability": "pure",
     "type": "function"
   },
   {

packages/contracts-bedrock/src/L2/OptimismSuperchainERC20Beacon.sol

@@ -3,25 +3,19 @@ pragma solidity 0.8.15;
 
 import { IBeacon } from "@openzeppelin/contracts/proxy/beacon/IBeacon.sol";
 import { ISemver } from "src/universal/interfaces/ISemver.sol";
+import { Predeploys } from "src/libraries/Predeploys.sol";
 
-/// @custom:proxied
+/// @custom:proxied true
 /// @custom:predeployed 0x4200000000000000000000000000000000000027
 /// @title OptimismSuperchainERC20Beacon
 /// @notice OptimismSuperchainERC20Beacon is the beacon proxy for the OptimismSuperchainERC20 implementation.
 contract OptimismSuperchainERC20Beacon is IBeacon, ISemver {
-    /// @notice Address of the OptimismSuperchainERC20 implementation.
-    address internal immutable IMPLEMENTATION;
-
     /// @notice Semantic version.
-    /// @custom:semver 1.0.0-beta.1
-    string public constant version = "1.0.0-beta.1";
-
-    constructor(address _implementation) {
-        IMPLEMENTATION = _implementation;
-    }
+    /// @custom:semver 1.0.0-beta.2
+    string public constant version = "1.0.0-beta.2";
 
     /// @inheritdoc IBeacon
-    function implementation() external view override returns (address) {
-        return IMPLEMENTATION;
+    function implementation() external pure override returns (address) {
+        return Predeploys.OPTIMISM_SUPERCHAIN_ERC20;
     }
 }

packages/contracts-bedrock/test/L2/OptimismSuperchainERC20Beacon.t.sol

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.15;
+
+// Testing utilities
+import { Bridge_Initializer } from "test/setup/Bridge_Initializer.sol";
+
+// Libraries
+import { Predeploys } from "src/libraries/Predeploys.sol";
+import { IBeacon } from "@openzeppelin/contracts/proxy/beacon/IBeacon.sol";
+
+/// @title OptimismSuperchainERC20BeaconTest
+/// @notice Contract for testing the OptimismSuperchainERC20Beacon contract.
+contract OptimismSuperchainERC20BeaconTest is Bridge_Initializer {
+    /// @notice Sets up the test suite.
+    function setUp() public override {
+        super.enableInterop();
+        super.setUp();
+    }
+
+    /// @notice Test that calling the implementation function returns the correct implementation address.
+    function test_implementation_is_correct() public view {
+        IBeacon beacon = IBeacon(Predeploys.OPTIMISM_SUPERCHAIN_ERC20_BEACON);
+        assertEq(beacon.implementation(), Predeploys.OPTIMISM_SUPERCHAIN_ERC20);
+    }
+}

packages/contracts-bedrock/test/Predeploys.t.sol

@@ -32,7 +32,7 @@ contract PredeploysBaseTest is CommonTest {
     function _usesImmutables(address _addr) internal pure returns (bool) {
         return _addr == Predeploys.OPTIMISM_MINTABLE_ERC721_FACTORY || _addr == Predeploys.SEQUENCER_FEE_WALLET
             || _addr == Predeploys.BASE_FEE_VAULT || _addr == Predeploys.L1_FEE_VAULT || _addr == Predeploys.EAS
-            || _addr == Predeploys.GOVERNANCE_TOKEN || _addr == Predeploys.OPTIMISM_SUPERCHAIN_ERC20_BEACON;
+            || _addr == Predeploys.GOVERNANCE_TOKEN;
     }
 
     function test_predeployToCodeNamespace() external pure {