chore(deps): update docker/build-push-action digest to 64c9b14

Author: renovate[bot]

.github/workflows/dockerhub-publish.yml

@@ -25,7 +25,7 @@ jobs:
           images: syseleven/syseleven-exporter
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@14487ce63c7a62a4a324b0bfb37086795e31c6c1
+        uses: docker/build-push-action@64c9b141502b80dbbd71e008a0130ad330f480f8
         with:
           context: .
           file: ./Dockerfile