estimate_gas doesn't reflect changes in mirror-node

[konstantinabl]

Description

The mirror node endpoint contracts/call used to return estimation only for read-only smart contract calls. However, this has changed and now we can also get estimations for transfers, account creations etc. The changes are not reflected in the estimateGas method

Steps to reproduce

1. Call eth_estimateGas with a transaction transferring value between two accounts
2. You will not get the base cost of 21000 (0x5208)

Refactoring suggestions

We can keep the try/catch in our code and implement a retry mechanism. In case the mirror node is not available, we can retry the call for N number of attempts.
If there is still no response we can do the following:

1. For contract deploy the intrinsicGasCost method, from the precheck file, can be used
2. For contract call return some hardcoded value (TBD)
3. For anything else the base cost - 21000

Hedera network

other

Version

0.46.0

Operating system

None