chore: Accommodate jwt's minor and patch updates

[sato11]

Current specification in gemspec pins the jwt version to the latest released one, consequently setting an obstacle where users have to wait until twilio-ruby modifies gemspec and releases it in order to update jwt.

Although I truly appreciate that you are constantly updating this library, I think it would be better if it accommodates updating jwt independent of twilio-ruby.

Also this change will

• start to run CI against newer version of jwt when it releases one, meaning if there is any unexpected breaking change, the CI can catch it ideally
• cut off chores like #343 Updated jwt gem dependencies #372 and chore: Bump jwt version max version to 2.6 #626 until the next major update comes

As a reference which might help, oauth2 gem relies on jwt in this manner: https://rubygems.org/gems/oauth2

Checklist

• I acknowledge that all my contributions will be made under the project's license
• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the Contribution Guidelines and my PR follows them
• I have titled the PR appropriately
• I have updated my branch with the main branch
• I have added tests that prove my fix is effective or that my feature works
• I have added the necessary documentation about the functionality in the appropriate .md file
• I have added inline documentation to the code I modified

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[shrutiburman]

Thanks for the PR! We've added the review to our backlog to be prioritised. Pull requests and +1s on the issue summary will help it move up the backlog.

[woodhull]

@shrutiburman I took a look and the diff in the jwt gem and it seems unlikely that loosening the dependency will cause any issues -- but it is blocking our use of the jwt gem version we'd like to use.

[alex-damian-negru]

Also closes #633; noticed the PR after creating the issue 👀

[franzliedke]

Thanks! This would be great! 🙏🏼

We're looking forward to this change, as Dependabot is currently asking us to downgrade twilio-ruby by two major releases, just to let us upgrade the jwt gem.

[sealabcore]

🚀