[BIP-300] Change Snapshot to Weighted Voting

Motivation

Snapshot is currently set to force "Single Choice Voting" on every proposal. This is a blocker for entities like veBAL wrappers who might want a way to reflect pass-through votes accurately. Ultimately we lose no functionality by making this change since voters can select one option with 100% of their voting weight and it would be as it is today - but we gain some additional use cases like wrapper pass through votes in case those organizations decide to make use of it.

Specification

If approved, the DAO Multisig (which is set as admin of the snapshot space) will initiate a transaction to change "Type" from "Single Choice Voting" to "Weighted Voting" in the Settings -> Voting menu via the snapshot gnosis safe app.