add the eth_baseFee call

[rvullriede]

What does this PR do?

Add another RPC call call "eth_baseFee".

Where should the reviewer start?

Ethereum.java

Why is it needed?

Some EVM-Chains (e.g. Avalanche, see https://docs.avax.network/quickstart/transaction-fees) provide a dedicated RPC call that returns the current base fee. This allows web3j to use such networks as a evm-compatible client that is not restricted to Ethereum alone.

[NickSneo]

@rvullriede Can you add some tests for your feature?

[rvullriede]

@NickSneo I've added a basic test for this. I also looked at the TransactionDecoderTests but that would require adding the baseFee also to the Transaction1559 (which it technically is) and I'm not sure if you'd support such a bigger change since I assume your main focus is Ethereum, right?

[NickSneo]

@NickSneo I've added a basic test for this. I also looked at the TransactionDecoderTests but that would require adding the baseFee also to the Transaction1559 (which it technically is) and I'm not sure if you'd support such a bigger change since I assume your main focus is Ethereum, right?

I think this is good enough, as eth_baseFee api is exclusive to some evm-clients like Avalanche only

[NickSneo]

LGTM

[NickSneo]

@rvullriede Plz add one more test in ResponseTest.java file, just like this - https://github.com/web3j/web3j/blob/99fb8f7512a110a61a1ca4ac6d3a9563c7ccbc46/core/src/test/java/org/web3j/protocol/core/ResponseTest.java#L191

[rvullriede]

Thx for the hint! Done :-)

[NickSneo]

Thx for the hint! Done :-)

pipeline is failing, plz run spotlessApply. Thanks

[rvullriede]

Thx for the hint! Done :-)

pipeline is failing, plz run spotlessApply. Thanks

Sorry for the noise. Done.