chore: reinstate wallet in upgrade.go (#10350)

refs: #9404 
refs: #10336
refs: #10319



## Description

#10319 cleaned up some dead code in smartWallets, and expected the changes to be included in Upgrade 18, because the smartWallet proposal was included in `upgrade.go`. #10336 cleaned up proposals that were left over from Upgrade 17. This reinstates the upgrade for wallets.

### Security Considerations

The cleaned up code is benign. it was designed to run once and has served its purpose. Removing it shouldn't affect anything.

### Scaling Considerations

No scaling consequences.

### Documentation Considerations

None

### Testing Considerations

The wallet upgrade was included in A3P-integration testing until three days ago. #10319 has been tested since 5 days ago without incident. removing benign dead code doesn't require extra tests.

### Upgrade Considerations

There is no *requirement* that this change be included in U18, so if it causes problems or gives anyone the willies, it can wait for the next release, but it's ready now.

a3p-integration/proposals/n:upgrade-next/initial.test.js

@@ -8,7 +8,7 @@ const vats = {
   localchain: { incarnation: 1 },
   orchestration: { incarnation: 0 },
   transfer: { incarnation: 1 },
-  walletFactory: { incarnation: 4 },
+  walletFactory: { incarnation: 5 },
   zoe: { incarnation: 3 },
 };
 

golang/cosmos/app/upgrade.go

@@ -191,6 +191,10 @@ func unreleasedUpgradeHandler(app *GaiaApp, targetUpgrade string) func(sdk.Conte
                 vm.CoreProposalStepForModules(
                     "@agoric/builders/scripts/vats/revive-kread.js",
                 ),
+				vm.CoreProposalStepForModules(
+					// Upgrade to include a cleanup from https://github.com/Agoric/agoric-sdk/pull/10319
+					"@agoric/builders/scripts/smart-wallet/build-wallet-factory2-upgrade.js",
+				),
 			}
 		}