[BIP-481] Claim and Lock Balancer DAO Aura allocation into vlAura

Payload with PR: https://github.com/BalancerMaxis/multisig-ops/pull/618 Summary:

Back when Aura launched, a portion of the supply was allocated to the Balancer DAO. That vested Aura exists in the following vesting contract: https://etherscan.io/address/0xfd72170339ac6d7bdda09d1eaca346b21a30d422#code We are proposing to lock the 1.4m aura that has been vested.

Motivation:

At the time of writing, 1.4m Aura has vested with 600k Aura left unvested. We are proposing to lock this into vlAura to begin earning rewards and eventually start allocating vote weight towards revenue generating or strategically important pools that lack a proper means of bootstrapping without ecosystem stakeholders voting philanthropically. A proposal for how the DAO will deal with allocating this vlAura voting power will be presented in the coming weeks, but we think it is prudent to initiate the locking now.

Specification:

The DAO multisig on mainnet 0x10A19e7eE7d7F8a52822f6817de8ea18204F2e4f will call the claim() function on the AuraVestedEscrow at 0xfd72170339ac6d7bdda09d1eaca346b21a30d422 with the parameter _lock set to true.