Refactor Genesis State Functions in Testing Utilities

We have multiple genesis state functions for different testing utilities in the codebase. Some of these functions can potentially be refactored for simplicity. Please review and refactor the functions as needed.\n\nRelevant PR: https://github.com/evmos/os/pull/37\nComment: https://github.com/evmos/os/pull/37#discussion_r1724489047