Check Payload Commit before accepting DAVotes

[bfish713]

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Fernando noted during the creation of specs that we don't ever check that DA votes are for the same commitment as the block we proposed. We technically don't need this as only a bad DA committee would vote for a Fake block. We'll end up proposing to the quorum with a payload that doesn't match certificate we formed from the fake votes. We won't get quorum votes, and thus the fake block commitment will never make it on chain. This hole doesn't open us up to anything besides allowing a bad committee to timeout a view (which it can already do by just not voting at all).

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