[BUG BOUNTY] [Gas Optimization] Use custom errors instead of revert strings to save gas.

[Sechunt3r]

Vulnerable URL: https://github.com/masa-finance/masa-contracts-identity/blob/main/contracts/SoulLinker.sol

Description:
Well, the contract SoulLinker has a solidity version of 0.8.7 and uses a lot of require statements for errors. But a solidity version that is greater than 0.8.4 can use custom errors to save gas. In this contract
the require statement use more gas per iteration. Instead of using strings for error messages, you can use custom
errors to reduce both deployment and runtime gas costs. In addition, they are very convenient as you can easily pass
dynamic information to them. By this, you can save a lot of gas.

┆Issue is synchronized with this Jira Bug by Unito