contracts-bedrock: Address review comments

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

@@ -224,7 +224,7 @@ contract Deploy is Deployer {
     ////////////////////////////////////////////////////////////////
 
     /// @notice Deploy a full system with a new SuperchainConfig
-    ///         The Superchain system has 3 singleton contracts which lie outside of an OP Chain:
+    ///         The Superchain system has 2 singleton contracts which lie outside of an OP Chain:
     ///         1. The SuperchainConfig contract
     ///         2. The ProtocolVersions contract
     function setupSuperchain() public {

packages/contracts-bedrock/src/L1/SuperchainConfig.sol

@@ -4,7 +4,6 @@ pragma solidity 0.8.15;
 import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
 import { ISemver } from "src/universal/ISemver.sol";
 import { Storage } from "src/libraries/Storage.sol";
-import { Constants } from "src/libraries/Constants.sol";
 
 /// @custom:audit none This contracts is not yet audited.
 /// @title SuperchainConfig

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

@@ -44,7 +44,7 @@ contract SuperchainConfig_Pause_Test is CommonTest {
         vm.expectEmit(address(superchainConfig));
         emit Paused("identifier");
 
-        vm.prank(cfg.portalGuardian());
+        vm.prank(superchainConfig.guardian());
         superchainConfig.pause("identifier");
 
         assertTrue(superchainConfig.paused());