[RPC] zkevm_consolidatedBlockNumber crashes when only batch 0

[tclemos]

System information

Erigon version: any

Premise: All CDK networks are supposed to have Batch 0 and Block 0 generated via genesis, which are assumed to be virtualized and verified.
Even though this scenario will only happen once per network, this is important for integrated tests that depend on empty networks to run tests.

Steps to reproduce:

• With a brand new CDK network without any new batch or block, just batch and block 0, send the following request:

{
	"jsonrpc":"2.0",
	"method":"zkevm_consolidatedBlockNumber",
	"params":[],
	"id":83
}

expected response:

{
    "jsonrpc": "2.0",
    "id": 83,
    "result": "0x0"
}

actual response

{
    "jsonrpc": "2.0",
    "id": 83,
    "error": {
        "code": -32000,
        "message": "method handler crashed"
    }
}