feat: sign without hash

[JuyeonYu]

Summary of Changes

For signing, add bool value using hash or not .
There is the same bool argument for Web3j for Java.
This PR will help collaborate with Java developers.

[yaroslavyaroslav]

@JuyeonYu thank for your participation, there's just a few requests about that:

1. Could you please to not recreate PRs, but update the excited ones if it's required.
2. I speculate that you're confused with the failing ci/cd. It has failed on code styling checked with a swiftlint. Please check the swiftlint config, and try to run it locally to figure what exactly its rule violated within tour pr.
3. The last but the most important, please elaborate the reasoning of this PR, it's really opaque for me so far.

[JuyeonYu]

@yaroslavyaroslav Hello. sorry for my insufficient reason and the others.
and for the failing ci/cd, I added default value for the new argument.

nowadays I collaborate with Java developers for making DAPP.
and of course, the differences between web3j for Java and web3swift are being discovered day by day.

In this PR, I added 'useHash' argument in making signature function.
the reason is why in the web3j for Java, there is the argument.
So when they make a signature without hash, we can't verify signature each other.

[yaroslavyaroslav]

I'm fine with that. What about you folks? @janndriessen @JeneaVranceanu

[JeneaVranceanu]

I'll add documentation to functions in Web3Signer and then we are ready to merge.