Update with the ruby 3.4 stable release (#254)

Keep .ruby-version until which is updated by nixpkgs

Author: kachick

.github/workflows/spec.yml

@@ -25,7 +25,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-24.04]
-        ruby: ['head', '3.3', '3.2']
+        ruby: ['head', '3.4', '3.3']
         gemfile: ['Gemfile', 'gemfiles/oldest.gemfile']
     runs-on: ${{ matrix.os }}
     env: # $BUNDLE_GEMFILE must be set at the job level, so it is set for all steps

.rubocop.yml

@@ -2,7 +2,7 @@ require:
   - rubocop-rake
 
 AllCops:
-  TargetRubyVersion: 3.2
+  TargetRubyVersion: 3.3
   DisplayCopNames: true
   Exclude:
     - '**/vendor/**/*'

README.md

@@ -18,7 +18,7 @@ I hope this might be a choice to integrate `PowerAssert` in RSpec.
 
 Require following dependencies
 
-- Ruby 3.2 or higher # Tested only in the head and last 2 rubies
+- Ruby 3.3 or higher # Tested only in the head and last 2 rubies
 - [rspec](https://rubygems.org/gems/rspec/)
 - [power_assert](https://rubygems.org/gems/power_assert)
 - [irb](https://rubygems.org/gems/irb) # To colorize

rspec-matchers-power_assert_matchers.gemspec

@@ -25,7 +25,7 @@ Gem::Specification.new do |gem|
   gem.add_dependency('power_assert', '>= 2.0.3', '< 3.0')
   gem.add_dependency('irb', '>= 1.4.0', '< 2.0') # To colorize
 
-  gem.required_ruby_version = '>= 3.2'
+  gem.required_ruby_version = '>= 3.3'
 
   # common