We were putting the unsigned/VM message through the pipeline.
The events index was storing the _unsigned_ message CID.
However, the Eth tx hash index maps signed Delegated-signature message
CIDs to transaction hashes, i.e. it uses the _signed_ message CID.
As a result, eth_getLogs and other log-related methods were
unable to resolve the transaction hash from the index properly, and
would end up returning 0x00..00 in the transactionHash field.
