Validator client does not ask for committee index 0 on attestation data request #8046
Description
Post electra validator clients are expected to ask only for attestation data with committee index 0.
It seems like here Lighthouse should ask for 0, instead of the actual committee_index. Ideally, in cases where there are multiple keys serviced by the validator client that need to attest in the given slot, it should not repeat multiple times the same request with the same data.
N.B.: Currently, the validator client is getting successful responses, because the beacon nodes are usually disregarding this field and are simply returning the data. However, when the validator client is managing a lot of keys, i.e.: 960, it is sending on average 30x more requests to the beacon node than necessary.