Upgrade deprecated action

Author: tagliala

.github/workflows/ci.yml

@@ -46,7 +46,7 @@ jobs:
       RAILS_VERSION: ${{ matrix.rails }}
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: Set up Ruby ${{ matrix.ruby }}
       uses: ruby/setup-ruby@v1
       with: