Ruby 4 support

[sfnelson]

Could not find compatible versions

Because json_api_client >= 1.23.0 depends on faraday-gzip >= 1.0, < 3.0
  and faraday-gzip < 3.0.0 depends on Ruby >= 2.6, < 4,
  json_api_client >= 1.23.0 requires Ruby >= 2.6, < 4.
So, because Gemfile depends on json_api_client >= 1.23.0
  and current Ruby version is = 4.0.1,
  version solving has failed.

faraday-gzip drops support for Ruby < 3 and adds requires Faraday 2. Any reason for pinning < 3.0 or is it reasonable to remove the constraint?

[sfnelson]

#416