drop support for Ruby 2.6

Also require ruby 2.7 or higher

Author: Geromendez135

.github/workflows/rspec_rubocop.yml

@@ -18,8 +18,6 @@ jobs:
     strategy:
       matrix:
         include: # use bundler 2.3 for ruby versions < 2.6 (https://bundler.io/compatibility.html)
-        - ruby-version: '2.6'
-          bundler-version: latest
         - ruby-version: '2.7'
           bundler-version: latest
         - ruby-version: '3.0'

rubocop-airbnb/rubocop-airbnb.gemspec

@@ -15,7 +15,7 @@ Gem::Specification.new do |spec|
   spec.license = 'MIT'
   spec.version = RuboCop::Airbnb::VERSION
   spec.platform = Gem::Platform::RUBY
-  spec.required_ruby_version = '>= 2.5'
+  spec.required_ruby_version = '>= 2.7'
 
   spec.require_paths = ['lib']
   spec.files = Dir[