Add cgi gem to dependencies

[schinery]

The cgi gem has been removed from the defaults in Ruby 4.0.

As it is required by this gem, this PR is adding it as a gem dependency.

Resolves #478.

[yatryan]

Just ran into this myself. We should probably consider adding ruby 4.0 to the Github Actions to "prove" the fix.

[schinery]

Just ran into this myself. We should probably consider adding ruby 4.0 to the Github Actions to "prove" the fix.

Added 4.0 to the CI test matrix here: 3d581bf

[bobbrodie]

Thanks @schinery , @yatryan ! I'll work on getting this into the next release.

[bobbrodie]

Hey @schinery , I made two small updates on sumoheavy/jira-ruby:add-cgi-dependency:

1. Set Rubocop to run on Ruby 3.4
2. Addressed RSpec/LeakyLocalVariable: Do not use local variables defined outside of examples inside of them.

When you have a moment, could you update your branch so those changes are pulled in, then I'll merge? Thanks!

[schinery]

When you have a moment, could you update your branch so those changes are pulled in, then I'll merge? Thanks!

All done @bobbrodie