remove deprecated rubies

Author: phumpal

.travis.yml

@@ -5,11 +5,10 @@ cache:
 - bundler
 before_install:
   - sudo iptables -L DOCKER || ( echo "DOCKER iptables chain missing" ; sudo iptables -N DOCKER )
-  - gem install bundler -v 1.15.1
+  - gem install bundler -v 1.17.3
 install:
 - bundle install
 rvm:
-- 2.3.0
 - 2.4.1
 notifications:
   email:

CHANGELOG.md

@@ -4,6 +4,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 This CHANGELOG follows the format listed [here](https://github.com/sensu-plugins/community/blob/master/HOW_WE_CHANGELOG.md).
 
 ## [Unreleased]
+- Remove EOL Rubies (@phumpal)
 
 ## [2.4.0] - 2019-10-04
 ### Added

sensu-plugins-postgres.gemspec

@@ -28,7 +28,7 @@ Gem::Specification.new do |s| # rubocop:disable Metrics/BlockLength
   s.platform               = Gem::Platform::RUBY
   s.post_install_message   = 'You can use the embedded Ruby by setting EMBEDDED_RUBY=true in /etc/default/sensu'
   s.require_paths          = ['lib']
-  s.required_ruby_version  = '>= 2.3.0'
+  s.required_ruby_version  = '>= 2.4.0'
 
   s.summary                = 'Sensu plugins for postgres'
   s.test_files             = s.files.grep(%r{^(test|spec|features)/})
@@ -37,15 +37,14 @@ Gem::Specification.new do |s| # rubocop:disable Metrics/BlockLength
   s.add_runtime_dependency 'sensu-plugin', '~> 1.2'
 
   s.add_runtime_dependency 'dentaku',      '2.0.4'
-  s.add_runtime_dependency 'pg',           '0.18.3'
+  s.add_runtime_dependency 'pg',           '1.1'
 
   s.add_development_dependency 'bundler',                   '~> 1.7'
   s.add_development_dependency 'codeclimate-test-reporter', '~> 1.0'
   s.add_development_dependency 'github-markup',             '~> 3.0'
   s.add_development_dependency 'kitchen-docker',            '~> 2.6'
   s.add_development_dependency 'kitchen-localhost',         '~> 0.3'
-  # locked to keep ruby 2.1 support, this is pulled in by test-kitchen
-  s.add_development_dependency 'mixlib-shellout',           ['< 2.3.0', '~> 2.2']
+  s.add_development_dependency 'mixlib-shellout',           '~> 2.4'
   s.add_development_dependency 'pry',                       '~> 0.10'
   s.add_development_dependency 'rake',                      '~> 12.3'
   s.add_development_dependency 'redcarpet',                 '~> 3.2'