FInalise the design of eth_getTransactionCount for Contracts

[Daniel-K-Ivanov]

Problem
Nonces for a contract are 1 + n where n is the number of times the contract created other contracts through CREATE or CREATE2. The deployment of the contract itself is considered part of the nonce, that's why the nonce starts from 1.

Currently eth_getTransactionCount for contracts returns hardcoded value of 1.

Solution
Clear out how services will handle nonces for contracts and whether they will do something with nonces. Once the design is defined, a discussion on how to handle them on the relay side must be conducted.

A potential solution for services -> Update the nonce of the contract for every CREATE / CREATE2 opcode executed from it.

[Kalina-Todorova]

Filed a ticket in hedera-services to address this: hashgraph/hedera-services#3640