ci.yml in danger-textlint-2.0.1

- old
+ new

@@ -5,15 +5,15 @@
   test:
     name: Test
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        image: [ 'ruby:2.4', 'ruby:2.5', 'ruby:2.6' ]
+        image: [ 'ruby:2.5', 'ruby:2.6', 'ruby:2.7' ]
     container:
       image: ${{ matrix.image }}
 
     steps:
-    - uses: actions/checkout@master
+    - uses: actions/checkout@v2
 
     - name: Setup bundler
       run: gem install bundler
     
     - name: bundle install