chore(ci): bump versions of all GitHub Action

- actions/checkout@v4 (v4.1.7)
- sigstore/cosign-installer@v3 (v3.6.0),
  sigstore/[email protected]
- docker/setup-buildx-action@v3 (v3.6.1)
- docker/login-action@v3 (v3.3.0)
- docker/metadata-action@v5 (v5.5.1)
- docker/build-push-action@v6 (v6.8.0)

Signed-off-by: Stephan Linz <[email protected]>

.github/workflows/docker-publish.yml

@@ -1,12 +1,16 @@
 name: Docker
 
+# Based on GitHub actions starter workflow for Docker publishing:
+# https://github.com/actions/starter-workflows/blob/main/ci/docker-publish.yml
+
 # This workflow uses actions that are not certified by GitHub.
 # They are provided by a third-party and are governed by
 # separate terms of service, privacy policy, and support
 # documentation.
 
 on:
   schedule:
+    # every day at 16:15 UTC
     - cron: '15 16 * * *'
   push:
     branches: [ "main" ]
@@ -21,7 +25,6 @@ env:
   # github.repository as <account>/<repo>
   IMAGE_NAME: ${{ github.repository }}
 
-
 jobs:
   build:
 
@@ -35,26 +38,29 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       # Install the cosign tool except on PR
       # https://github.com/sigstore/cosign-installer
       - name: Install cosign
         if: github.event_name != 'pull_request'
-        uses: sigstore/cosign-installer@f3c664df7af409cb4873aa5068053ba9d61a57b6 #v2.6.0
+        uses: sigstore/cosign-installer@v3
         with:
-          cosign-release: 'v1.13.1'
+          cosign-release: 'v2.4.0'
+      - name: Check cosign installation
+        run: cosign version
 
-
-      # Workaround: https://github.com/docker/build-push-action/issues/461
-      - name: Setup Docker buildx
-        uses: docker/setup-buildx-action@79abd3f86f79a9d68a23c75a09a9a85889262adf
+      # Set up BuildKit Docker container builder to be able to build
+      # multi-platform images and export cache
+      # https://github.com/docker/setup-buildx-action
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
 
       # Login against a Docker registry except on PR
       # https://github.com/docker/login-action
       - name: Log into registry ${{ env.REGISTRY }}
         if: github.event_name != 'pull_request'
-        uses: docker/login-action@28218f9b04b4f3f62068d7b6ce6ca5b26e35336c
+        uses: docker/login-action@v3
         with:
           registry: ${{ env.REGISTRY }}
           username: ${{ github.actor }}
@@ -64,15 +70,15 @@ jobs:
       # https://github.com/docker/metadata-action
       - name: Extract Docker metadata
         id: meta
-        uses: docker/metadata-action@98669ae865ea3cffbcbaa878cf57c20bbf1c6c38
+        uses: docker/metadata-action@v5
         with:
           images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
 
       # Build and push Docker image with Buildx (don't push on PR)
       # https://github.com/docker/build-push-action
       - name: Build and push Docker image
         id: build-and-push
-        uses: docker/build-push-action@ac9327eae2b366085ac7f6a2d02df8aa8ead720a
+        uses: docker/build-push-action@v6
         with:
           context: .
           push: ${{ github.event_name != 'pull_request' }}
@@ -81,7 +87,6 @@ jobs:
           cache-from: type=gha
           cache-to: type=gha,mode=max
 
-
       # Sign the resulting Docker image digest except on PRs.
       # This will only write to the public Rekor transparency log when the Docker
       # repository is public to avoid leaking data.  If you would like to publish
@@ -90,7 +95,8 @@ jobs:
       - name: Sign the published Docker image
         if: ${{ github.event_name != 'pull_request' }}
         env:
-          COSIGN_EXPERIMENTAL: "true"
+          TAGS: ${{ steps.meta.outputs.tags }}
+          DIGEST: ${{ steps.build-and-push.outputs.digest }}
         # This step uses the identity token to provision an ephemeral certificate
         # against the sigstore community Fulcio instance.
-        run: echo "${{ steps.meta.outputs.tags }}" | xargs -I {} cosign sign {}@${{ steps.build-and-push.outputs.digest }}
+        run: echo "${TAGS}" | xargs -I {} cosign sign --yes {}@${DIGEST}