Relax ruby version dependency check

[makevoid]

Allow this gem to be used with ruby 3

if you need I can bump the gem version as well in this PR or any other changes, let me know

[makevoid]

anyone interested in this gem working with ruby 3?

[q9f]

anyone interested in this gem working with ruby 3?

I stepped up: https://github.com/q9f/keccak.rb - note, I renamed it to keccak to further distinguish it from the final sha3 standard.

[mathieujobin]

~~I'm not interested refactoring my code to use the renamed fork. So I am using this branch. THank you~~

It turns out, I have two projects that are using this lib. One is using this branch. And the other one I moved to keccak. Eventually, I'll have both use keccak, but for now everything works, so I am not touching anything.

[elissonmichael]

anyone interested in this gem working with ruby 3?

I stepped up: https://github.com/q9f/keccak.rb - note, I renamed it to keccak to further distinguish it from the final sha3 standard.

Thanks.