bump gha version numbers, fix deprecation notices (#85)

.github/workflows/main.yml

@@ -24,7 +24,7 @@ jobs:
     steps:
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Extract branch name
         id: extract_branch
@@ -36,17 +36,17 @@ jobs:
 
       - name: Set up Docker Buildx
         id: buildx
-        uses: docker/setup-buildx-action@v2
+        uses: docker/setup-buildx-action@v3
 
       - name: Login to Docker Hub
-        uses: docker/login-action@v2
+        uses: docker/login-action@v3
         with:
           username: ${{ secrets.DOCKER_HUB_USERNAME }}
           password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}      
 
       - name: Build and push
         id: docker_build
-        uses: docker/build-push-action@v3
+        uses: docker/build-push-action@v6
         with:
           context: ./
           file: ./docker/CI.Dockerfile