Increase the required ruby version to v2.6

This is the only unsupported version which is still listed in the
offical Ruby download page, so it seems like a good choice for the
required ruby.

This eliminates support for v2.5, and I have also it from CI as well.

.github/workflows/ci.yml

@@ -6,7 +6,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest]
-        ruby: ['2.5', '2.6']
+        ruby: ['2.6']
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v3

.gitignore

@@ -28,7 +28,6 @@ build/
 # for a library or gem, you might want to ignore these files since the code is
 # intended to run in multiple environments; otherwise, check them in:
 Gemfile.lock
-.ruby-version
 .ruby-gemset
 
 # unless supporting rvm < 1.11.0 or doing something fancy, ignore this:

.rubocop.yml

@@ -1,5 +1,8 @@
 require: rubocop-rspec
 
+AllCops:
+  TargetRubyVersion: 2.6
+
 Metrics/LineLength:
   Max: 100
 

.ruby-version

@@ -0,0 +1 @@
+2.6.10

CHANGELOG.md

@@ -5,6 +5,8 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Changed
+- update the required ruby version from v2.2 to v2.6
 
 ## [0.0.3] - 2022-01-24
 ### Added

rspec-tabular.gemspec

@@ -22,7 +22,7 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ['lib']
 
-  spec.required_ruby_version = '>= 2.5.0'
+  spec.required_ruby_version = '>= 2.6.0'
 
   spec.add_runtime_dependency     'rspec-core', '>= 2.99.0'