Update ci.yml

Author: jason-fox

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
   #   runs-on: ubuntu-latest
   #   steps:
   #     - name: Git checkout
-  #       uses: actions/checkout@v2
+  #       uses: actions/checkout@v3
   #     - name: Use Java 11
   #       uses: actions/setup-java@v1
   #       with:
@@ -28,7 +28,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Git checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Run DITA-OT Unit Test
         uses: jason-fox/dita-unit-test-action@master
         with: