chore(deps): update docker/setup-buildx-action action to v4

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/continuous-integration.yml

@@ -22,7 +22,7 @@ jobs:
       - uses: actions/checkout@v6
 
       - name: Set up Docker
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Start DB2 container
         run: |