fix: Use hex string for blockNumber param in eth_getBlockReceipts

[lyfsn]

This eth method eth_getBlockReceipts needs a hex string value block number as the first parameter.

Before this code is fixed, this error will occur.

2024/03/11 10:17:41 error doing requestReceipts for slot 43215: io-error when fetching tx-receipts: invalid argument 0: json: cannot unmarshal number into Go value of type string

[ohko4711]

@danielCalbonero12345 @guybrush hi,

Although RECEIPTS_MODE_BATCH can be used to circumvent this issue, merging this PR can maintain consistency of our code repo and the upstream. Any questions are welcome for further discussion