Add check for EthGetLogs return explicit error when queried for not-existing block hash

[snissn]

filecoin-project/lotus#10940

query for a non existent block hash and validate whether we see

    "error": {
        "code": -32000,
        "message": "unknown block"
    }

if so the test passes

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for deeper context

filecoin-project/lotus#12293