Remove support for Ruby 2.6 and add Ruby 3.4

Author: alexrudall

.circleci/config.yml

@@ -38,7 +38,6 @@ workflows:
           matrix:
             parameters:
               ruby-image:
-                - cimg/ruby:2.6-node
                 - cimg/ruby:2.7-node
                 - cimg/ruby:3.0-node
                 - cimg/ruby:3.1-node

Gemfile

@@ -9,5 +9,5 @@ gem "dotenv", "~> 3.1.7"
 gem "rake", "~> 13.2.1"
 gem "rspec", "~> 3.13"
 gem "rubocop", "~> 1.74.0"
-gem "vcr", "~> 6.1" # 6.2 requires Ruby 2.7 or greater, so specs for 2.6 will fail.
+gem "vcr", "~> 6.3.1"
 gem "webmock", "~> 3.25.1"

Gemfile.lock

@@ -91,7 +91,7 @@ DEPENDENCIES
   rspec (~> 3.13)
   rubocop (~> 1.74.0)
   ruby-openai!
-  vcr (~> 6.1)
+  vcr (~> 6.3.1)
   webmock (~> 3.25.1)
 
 BUNDLED WITH