Move to broadcast_tx_sync() for IBC transactions and keep track of account sequence

[ancazamfir]

Crate

relayer

Summary

Move to broadcast_tx_sync() for IBC transactions

Problem Definition

hermes uses broadcast_tx_commit() to send IBC messages. While it bulks multiple messages in a transaction, it can only include one Tx per block for a given chain.
We should move to using broadcast_tx_sync() instead and keep track of account sequence.

Issues that may be addressed:
#919 - account sequence mismatch
#930, #938 - out of gas issues, incorrect bulking
#977 - broadcast_tx_commit timeout
#978 - account sequence mismatch

Proposal

Acceptance Criteria

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For Admin Use

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