Upgrade to Faraday 2.x

[Ginja]

• Update default Ruby installation to 2.7.2. Keeping the required_ruby_version set to '>= 2.6' as this gem does still work with 2.6.6.
• Cherry-picked @cuchi's commit from their PR. It's fairly common now for other gems to require Faraday > 2 and that conflicts when those gems are used in conjunction with oktakit.

🎩 tests pass locally

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136 examples, 0 failures

[rporrasluc]

Hello @Ginja, as I have commented via Slack:

In principle changes look good, however, all applications using oktakit will need to get faraday bumped. Can we set the gem so faraday 1 is still supported while we also allow other versions? Something like spec.add_dependency('faraday', '>= 0.17.3', '< 3')?

From what I can see in this Gemfile.lock as example it's very common to gem defining the dependency like that.

You might need to create version conditioned code like this from octokit.

What do you think?

[Ginja]

As per our discussion with @ltk we'll keep the minimum Faraday requirement at version 2 to try and prevent similar issues that we experienced in past PRs. Afterwards I'll cut a new major release (i.e. 1.0.0).