/account/balance staking support

[AlanVerbner]

As we will be introducing staking functionality, we also need to be able to return staking account balances. We need to provide the balance of a staking account at a certain block number. To do so, we need to let people to query for an account based on a stake address.

The response format should not change but different tables will need to be queried when looking for a stake address.

1. This query could be used as as a starting point although don't forget to consider the withdrawals.
2. We can switch thery by address bech32 preffix (stake, stake_test)
3. Update src/server/services/block-service.ts#findUtxoByAddressAndBlock to:
   1. Switch based on the address type and perform different queries
   2. Update the interface to return something for stake and non stake accounts.
   3. Update src/server/utils/data-mapper.ts#mapToAccountBalanceResponse to properly map the new type (do not include utxos in case of staking

Testing

As mentioned in #208 we cannot use a db-snapshot therefore some blocks will need to be inserter to fake data.

1. Check our e2e suite is still working (no actions needed)
2. Add new tests to the current ones. To do so, we will need to manually insert a fake blocks:
   • A block were a reward is received
   • A block were another reward is received (in order to test the sum is working)
   • A block with a withdrawal to check staking account balance has been reduced
3. We need to be make sure rosetta-cli check:data still works
   1. Deploy the new version (using the commit as build context for docker) on our mainnet testing server.
   2. Execute check:data for a block range containing block TBD.
   3. Execute check:data for the whole chain.

[AlanVerbner]

Implemented here https://github.com/input-output-hk/cardano-rosetta/pull/213