Let's spell stripped correctly

[cclauss]

Summary of Changes

Fixes # (if applicable - add the number of issue this PR addresses)

Test Data or Screenshots

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[cclauss]

Should this be stripped or striped or some other word?

[JeneaVranceanu]

I'd actually name it publicKey as well.
Probably, it was intended to be named stripped as in an uncompressed form we remove the first byte of 65 bytes as it's a static prefix 0x04.

According to https://www.oreilly.com/library/view/mastering-ethereum/9781491971932/ch04.html (search for Table 4-1. Serialized EC public key prefixes) Ethereum only uses uncompressed public keys of 65 bytes in length where the first byte is always 04 and the compressed public keys have either 02 or 03 prefix. I'd suggest modifying the whole function to the following:

/// Convert a public key to the corresponding ``EthereumAddress``. Accepts public keys in compressed (33 bytes), uncompressed (65 bytes)
/// or uncompressed without prefix (64 bytes) format.
///
/// - Parameter publicKey: compressed 33, non-compressed (65 bytes) or non-compressed without prefix (64 bytes)
/// - Returns: 20 bytes of address data.
static func publicToAddressData(_ publicKey: Data) -> Data? {
    var publicKey = publicKey
    if publicKey.count == 33 {
        guard (publicKey[0] == 2 || publicKey[0] == 3),
              let decompressedKey = SECP256K1.combineSerializedPublicKeys(keys: [publicKey], outputCompressed: false) else {
            return nil
        }
        publicKey = decompressedKey
    }
    if publicKey.count == 65 {
        guard publicKey[0] == 4 else {
            return nil
        }
        publicKey = publicKey[1...64]
    } else if publicKey.count != 64 {
        return nil
    }
    let sha3 = publicKey.sha3(.keccak256)
    let addressData = sha3[12...31]
    return addressData
}

[JeneaVranceanu]

@cclauss I've updated your PR. Will push test cases in a separate one.

[JeneaVranceanu]

Test cases added in #751