Update rubyzip version

[kenzo-tanaka]

Hello @pythonicrubyist 👋
First of all, thank you for this nice gem!

I would like to use this gem, but it conflicts rubyzip dependency with other gem like docx.
So, could you update rubyzip dependency? 🙏

I checked that all tests pass.

$ bundle exec rspec
............

Finished in 0.09584 seconds (files took 0.16522 seconds to load)
12 examples, 0 failures

[mrhaddad]

+1