chore: update GitHub Actions to latest major versions (#879)

- actions/checkout v5 -> v7
- actions/setup-python v6 -> v7
- actions/configure-pages v5 -> v6
- actions/upload-pages-artifact v3 -> v5
- actions/deploy-pages v4 -> v5
- actions/upload-artifact v4 -> v7
- actions/download-artifact v4 -> v8
- docker/setup-qemu-action v3 -> v4
- docker/setup-buildx-action v3 -> v4
- docker/metadata-action v5 -> v6
- docker/login-action v3 -> v4
- docker/build-push-action v6 -> v7
- codecov/codecov-action v5 -> v7
- peter-evans/create-pull-request v7 -> v8

codecov/test-results-action (already replaced by codecov-action with
report_type: test_results) and pypa/gh-action-pypi-publish@release/v1
(moving branch, still the current major) need no change.

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

.github/workflows/docker.yml

@@ -40,17 +40,17 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v7
 
       - name: Set up QEMU
-        uses: docker/setup-qemu-action@v3
+        uses: docker/setup-qemu-action@v4
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Docker meta
         id: meta
-        uses: docker/metadata-action@v5
+        uses: docker/metadata-action@v6
         with:
           images: |
             ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
@@ -68,14 +68,14 @@ jobs:
         # workflow_dispatch runs build for validation only and must never
         # touch the registry, so they skip the login entirely.
         if: github.event_name == 'release' || inputs.push_image == true
-        uses: docker/login-action@v3
+        uses: docker/login-action@v4
         with:
           registry: ${{ env.REGISTRY }}
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           context: .
           platforms: linux/amd64,linux/arm64