Add more utilities to Utilities.sol

[StErMi]

@FrankieIsLost do you think that these methods I added could be useful to be added to your Utilities.sol contract?

https://github.com/StErMi/forge-damn-vulnerable-defi/blob/main/src/test/utils/Utilities.sol

I've added

• createUsers(uint256 userNum, uint256 initialFunds, string[] memory userLabels) that allow to create users specifying the amount of initial funds and the label to tag them
• createUsers(uint256 userNum, uint256 initialFunds that allow to create users specifying the amount of initial funds