Breaking eth_feeHistory API change in v1.11.0+

[michaelkaplan13]

There was a minor breaking change to the eth_feeHistory API introduced in v1.11.0.

Specifically in the this commit: 31d401e

Previously the blockCount parameter could be given as a number in JSON; now it must be given as a string.

This request body was previously valid:

{
    "jsonrpc": "2.0",
    "method": "eth_feeHistory",
    "params": [1, "latest", []],
    "id": 42
}

But now gives the error: invalid argument 0: json: cannot unmarshal number into Go value of type *math.HexOrDecimal64

It's a simple change, but it would be helpful to call this out in the release notes so any client implementations will know they need to make the change prior to upgrading.

[Moha19med88]

#26793