Update docker/setup-buildx-action action to v3.12.0

Author: renovate[bot]

.github/workflows/docker.yml

@@ -43,7 +43,7 @@ jobs:
       # multi-platform images and export cache
       # https://github.com/docker/setup-buildx-action
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@e468171a9de216ec08956ac3ada2f0791b6bd435 # v3.11.1
+        uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3.12.0
 
       # Login against a Docker registry except on PR
       # https://github.com/docker/login-action