singleton-deployment deploys to the wrong address

[Auryn Macmillan]

We've introduced some changes to ModuleProxyFactory.sol over the last year, meaning singleton-deployment now produces a different address. We should either:

1. revert the changes so that singleton-deployment produces the same address
2. mine a new vanity address using the current version and deploy it to each network, making sure to update everywhere relevant to the new factory address.