Do not convert CheckTx errors to ChainError event and remove the latter

[romac]

With sequential sending, we get the DeliverTX result before sending the next transaction. However it is a bit unclear here whether we should continue submitting the remaining batches to the chain, if DeliverTX or SendTX returns error.

Supposingly, we should probably short circuit and return on the first encounter of error. However I keep the behavior the same as the parallel version, so that we do not observe unexpected difference in behavior when sequential batching is enabled.

The anti-pattern behavior of converting errors to duplicate IBC error events also significantly complicates the design space here. So I'd rather leave the behavior untouched until the chain errors are handled in better ways.

Originally posted by @soareschen in #2543 (comment)