Remove authorization of owner in StakingProxy after init is called in constructor

contracts/staking/contracts/src/StakingProxy.sol

@@ -42,7 +42,15 @@ contract StakingProxy is
         MixinStorage()
     {
         readOnlyProxy = _readOnlyProxy;
+
+        // Deployer address must be authorized in order to call `init`
+        _addAuthorizedAddress(msg.sender);
+
+        // Attach the staking contract and initialize state
         _attachStakingContract(_stakingContract);
+
+        // Remove the sender as an authorized address
+        _removeAuthorizedAddressAtIndex(msg.sender, 0);
     }
 
     /// @dev Delegates calls to the staking contract, if it is set.

contracts/staking/contracts/src/immutable/MixinStorage.sol

@@ -139,12 +139,4 @@ contract MixinStorage is
 
     /// @dev The WETH balance of this contract that is reserved for pool reward payouts.
     uint256 public wethReservedForPoolRewards;
-
-    /// @dev Adds owner as an authorized address.
-    constructor()
-        public
-        Authorizable()
-    {
-        _addAuthorizedAddress(owner);
-    }
 }