Added build attestation to the workflow

.github/workflows/_docker-build.yml

@@ -46,6 +46,7 @@ jobs:
 
       - uses: docker/setup-buildx-action@v3
       - name: Build and push Docker image
+        id: push
         uses: docker/build-push-action@v5
         with:
           context: ${{ inputs.context }}
@@ -58,3 +59,10 @@ jobs:
             GIT_COMMIT_MESSAGE="${github.event.head_commit.message//\n/}"
           cache-from: type=gha
           cache-to: type=gha,mode=min
+      - name: Attest
+        uses: actions/attest-build-provenance@v1
+        id: attest
+        with:
+          subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          subject-digest: ${{ steps.push.outputs.digest }}
+          push-to-registry: true