chore(deps)(deps): bump docker/build-push-action from 6.19.2 to 7.1.0

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 6.19.2 to 7.1.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](10e90e3645...bcafcacb16)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-version: 7.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/publish-canvas-image.yml

@@ -85,7 +85,7 @@ jobs:
           echo "ws_url=${WS_URL}" >> "$GITHUB_OUTPUT"
 
       - name: Build & push canvas image to GHCR
-        uses: docker/build-push-action@10e90e3645eae34f1e60eeb005ba3a3d33f178e8 # v6
+        uses: docker/build-push-action@bcafcacb16a39f128d818304e6c9c0c18556b85f # v7.1.0
         with:
           context: ./canvas
           file: ./canvas/Dockerfile

.github/workflows/publish-workspace-server-image.yml

@@ -131,7 +131,7 @@ jobs:
       # drifted 10 days behind staging — same class of bug, different
       # mechanism.
       - name: Build & push platform image to GHCR (staging-<sha> + staging-latest)
-        uses: docker/build-push-action@10e90e3645eae34f1e60eeb005ba3a3d33f178e8 # v6
+        uses: docker/build-push-action@bcafcacb16a39f128d818304e6c9c0c18556b85f # v7.1.0
         with:
           context: .
           file: ./workspace-server/Dockerfile
@@ -155,7 +155,7 @@ jobs:
             org.opencontainers.image.description=Molecule AI platform (Go API server) — pending canary verify
 
       - name: Build & push tenant image to GHCR (staging-<sha> + staging-latest)
-        uses: docker/build-push-action@10e90e3645eae34f1e60eeb005ba3a3d33f178e8 # v6
+        uses: docker/build-push-action@bcafcacb16a39f128d818304e6c9c0c18556b85f # v7.1.0
         with:
           context: .
           file: ./workspace-server/Dockerfile.tenant