Use actions/checkout@v4 in GitHub Actions.

Author: fourdollars

.github/workflows/docker-publish.yml

@@ -26,7 +26,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Run tests
         run: |
@@ -47,7 +47,7 @@ jobs:
     if: github.event_name == 'push' || github.event_name == 'schedule'
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Build image
         run: docker build . --file Dockerfile --tag $IMAGE_NAME