Drop Ruby v2.2 and update Bundler to v2.1

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-20.04, macos-13]
-        ruby: [2.2, 2.3, 2.4, 2.5, 2.6, head, jruby, jruby-head]
+        ruby: [2.3, 2.4, 2.5, 2.6, head, jruby, jruby-head]
     continue-on-error: ${{ endsWith(matrix.ruby, 'head') || endsWith(matrix.ruby, 'jruby') }}
     runs-on: ${{ matrix.os }}
     steps:
@@ -19,7 +19,7 @@ jobs:
         ruby-version: ${{ matrix.ruby }}
         # HACK: Continue to use bundler <2 because of Ruby v2.2 support. Once the
         # lowest dependency is Ruby v2.3 we can consider upgrading to Bundler 2.x.
-        bundler: 1.14
+        bundler: 2.1
         bundler-cache: true
     - run: bundle exec rake spec
   coverage:
@@ -30,10 +30,10 @@ jobs:
     - uses: actions/checkout@v3
     - uses: ruby/setup-ruby@v1
       with:
-        ruby-version: '2.2'
+        ruby-version: '2.3'
         # HACK: Continue to use bundler <2 because of Ruby v2.2 support. Once the
         # lowest dependency is Ruby v2.3 we can consider upgrading to Bundler 2.x.
-        bundler: 1.14
+        bundler: 2.1
         bundler-cache: true
     - run: bundle exec rake
       env:

.ruby-version

@@ -1 +1 @@
-2.2.10
+2.3.8

rspec-side_effects.gemspec

@@ -21,11 +21,11 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ['lib']
 
-  spec.required_ruby_version = '>= 2.2.0'
+  spec.required_ruby_version = '>= 2.3.0'
 
   spec.add_runtime_dependency     'rspec-core', '>= 2.99.0'
 
-  spec.add_development_dependency 'bundler', '~> 1.14'
+  spec.add_development_dependency 'bundler', '~> 2.1'
   spec.add_development_dependency 'rake',    '~> 12.3'
   spec.add_development_dependency 'rspec',   '~> 3.0'