Only enabled macOS environment

Author: hsbt

azure-pipelines.yml

@@ -1,26 +1,4 @@
 jobs:
-- job: Linux
-  pool:
-    vmImage: 'ubuntu-16.04'
-  strategy:
-    matrix:
-      ruby 2.3:
-        ruby_version: '2.3.7'
-      ruby 2.4:
-        ruby_version: '2.4.4'
-      ruby 2.5:
-        ruby_version: '2.5.1'
-  steps:
-  - task: UseRubyVersion@0
-    inputs:
-      versionSpec: $(ruby_version)
-  - script: |
-      gem install bundler
-      bundle install --retry=3 --jobs=4
-    displayName: 'bundle install'
-  - script: ruby -Ilib exe/rake
-    displayName: 'ruby -Ilib exe/rake'
-
 - job: macOS
   pool:
     vmImage: 'macos-10.13'
@@ -31,23 +9,3 @@ jobs:
     displayName: 'bundle install'
   - script: ruby -Ilib exe/rake
     displayName: 'ruby -Ilib exe/rake'
-
-- job: Windows
-  pool:
-    vmImage: 'vs2017-win2016'
-  strategy:
-    matrix:
-      ruby 2.4:
-        ruby_version: '2.4.3'
-      ruby 2.5:
-        ruby_version: '2.5.0'
-  steps:
-  - task: UseRubyVersion@0
-    inputs:
-      versionSpec: $(ruby_version)
-  - script: |
-      gem install bundler
-      bundle install --retry=3 --jobs=4
-    displayName: 'bundle install'
-  - script: ruby -Ilib exe/rake
-    displayName: 'ruby -Ilib exe/rake'