[Feature Request]: allow user to set account sequence

[jcstein]

Implementation ideas

Users (including myself) have reported that they are hitting account sequence errors in posting blobs using celestia-node. The workaround for this is to set the correct account sequence. While it is possible to set the account sequence in celestia-app's binary, it isn't possible with celestia-node.

This feature's implementation would allow the user to send a transaction using celestia-node with a custom account sequence.