ethereum: fix core contract upgradeability

Missed initializer

ethereum/contracts/Implementation.sol

@@ -30,6 +30,10 @@ contract Implementation is Governance {
         setNextSequence(emitter, sequence + 1);
     }
 
+    function initialize() initializer public virtual {
+        // this function needs to be exposed for an upgrade to pass
+    }
+
     modifier initializer() {
         address implementation = ERC1967Upgrade._getImplementation();
 

ethereum/contracts/State.sol

@@ -46,4 +46,4 @@ contract Storage {
 
 contract State {
     Storage.WormholeState _state;
-}
+}

ethereum/contracts/bridge/BridgeState.sol

@@ -49,4 +49,4 @@ contract BridgeStorage {
 
 contract BridgeState {
     BridgeStorage.State _state;
-}
+}

ethereum/contracts/mock/MockImplementation.sol

@@ -6,10 +6,6 @@ pragma solidity ^0.8.0;
 import "../Implementation.sol";
 
 contract MockImplementation is Implementation {
-    function initialize() initializer public {
-        // this function needs to be exposed for an upgrade to pass
-    }
-
     function testNewImplementationActive() external pure returns (bool) {
         return true;
     }