Fix dependency warning in Ruby 3.3 and prepare for Ruby 3.4

[JunichiIto]

Fix #1642

[alexreisner]

Thanks for this! I will merge, but first, one thing. Because these gems are only required for specific lookups, we might want to indicate that with a comment at the end of each line (like # for :google_premier lookup). That way, if the lookups are removed in the future, we know we can remove the dependency too. Does that make sense?

[JunichiIto]

Thank you for your review. I added comments.