ci: Bump docker/build-push-action version

See https://github.com/docker/build-push-action/releases.

.github/actions/run-in-docker-action/action.yml

@@ -17,7 +17,7 @@ runs:
   steps:
     - uses: docker/setup-buildx-action@v3
 
-    - uses: docker/build-push-action@v5
+    - uses: docker/build-push-action@v6
       id: main_builder
       continue-on-error: true
       with:
@@ -26,7 +26,7 @@ runs:
         load: true
         cache-from: type=gha,scope=${{ inputs.scope }}
 
-    - uses: docker/build-push-action@v5
+    - uses: docker/build-push-action@v6
       id: retry_builder
       if: steps.main_builder.outcome == 'failure'
       with:

.github/workflows/ci.yml

@@ -67,7 +67,7 @@ jobs:
             network=host
 
       - name: Build container
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           file: ./ci/linux-debian.Dockerfile
           cache-from: type=gha,scope=${{ runner.arch }}