Simulated (not sent) txs are inserted into the rpc-server db

[spalladino]

Reported by @LHerskind. Txs are being added to the local RPC server DB on simulation here, whereas they should be added only when sending.

Also, it seems that tx hash is not being generated consistently. It could be due to a random nonce generation, but we should look into it to confirm:

It seems wrong that my tx hash changes between me simulating it and sending if I do:

const b = await deployedContract.methods.init().simulate({ origin: recipient });
const tx = deployedContract.methods.init().send({ origin: recipient });