Require Ruby >= 3.3 and update CI Ruby versions (#55)

* Require Ruby >= 3.3 and update CI Ruby versions

* Bump bundler to 4.0.15

Author: dduugg

.rubocop.yml

@@ -12,7 +12,7 @@ AllCops:
   NewCops: enable
   Exclude:
     - vendor/bundle/**/**
-  TargetRubyVersion: 2.6
+  TargetRubyVersion: 3.3
 
 Metrics/ParameterLists:
   Enabled: false

Gemfile.lock

@@ -114,4 +114,4 @@ DEPENDENCIES
   tapioca
 
 BUNDLED WITH
-   2.4.21
+   4.0.15

parse_packwerk.gemspec

@@ -21,7 +21,7 @@ Gem::Specification.new do |spec|
   # Specify which files should be added to the gem when it is released.
   spec.files = Dir['README.md', 'lib/**/*']
   spec.require_paths = ['lib']
-  spec.required_ruby_version = '>= 2.6'
+  spec.required_ruby_version = '>= 3.3'
 
   spec.add_dependency 'bigdecimal'
   spec.add_dependency 'sorbet-runtime'