JSON-RPC Filter eth_newBlockFilter returning incorrect block hashes when calling eth_getFilterChanges

[GAtom22]

System info: OS Ubuntu 20.04, Ethermint main branch and latest version

Steps to reproduce:

1. Create a new block filter with the JSON-RPC method eth_newBlockFilter
2. Call the JSON-RPC method eth_getFilterChanges to get an array of the latest block hashes. This is the expected result according to Ethereum docs.
3. Try to get block data usint the JSON-RPC method eth_getBlockByHash using one of the hashed returned in eth_getFilterChanges

Expected behavior: Should return information about the block

Actual behavior: Returns null

Additional info: This occurs because the returned array of hashes are not the correct block hashes.