ci.yml in knife-changelog-4.0.0

- old
+ new

@@ -3,10 +3,10 @@
 jobs:
   test:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby-version: ['2.5', '2.7']
+        ruby-version: ['3.1']
     steps:
     - uses: actions/checkout@v2
     - uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby-version }}