v4 actions

Author: davidfrantz

.github/workflows/docker-publish.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repo
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Docker login
         run: docker login -u $DOCKER_USER -p $DOCKER_PASSWORD
       - name: Build image