Update docker/metadata-action action to v6

Author: renovate[bot]

.github/workflows/build_test.yml

@@ -145,7 +145,7 @@ jobs:
 
       - name: Docker meta
         id: meta
-        uses: docker/metadata-action@v5
+        uses: docker/metadata-action@030e881283bb7a6894de51c315a6bfe6a94e05cf # v6
         with:
           # list of Docker images to use as base name for tags
           images: |