Fixes build action

.github/workflows/docker.yml

@@ -9,6 +9,7 @@ on:
 # Defines two custom environment variables for the workflow. These are used for the Container registry domain, and a name for the Docker image that this workflow builds.
 env:
   REGISTRY: ghcr.io
+  NAMESPACE: ${{ github.repository_owner }}
 
 # There is a single job in this workflow. It's configured to run on the latest available version of Ubuntu.
 jobs:
@@ -40,20 +41,21 @@ jobs:
         id: meta
         uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
         with:
-          images: ${{ env.REGISTRY }}/${{ matrix.image }}
+          images: ${{ env.REGISTRY }}/${{ env.NAMESPACE }}/${{ matrix.image }}
 
       - name: Build and push Docker image
         id: push
         uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
         with:
           context: .
           push: true
+          target: ${{ matrix.image }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
 
       - name: Generate artifact attestation
         uses: actions/attest-build-provenance@v1
         with:
-          subject-name: ${{ env.REGISTRY }}/${{ matrix.image }}
+          subject-name: ${{ env.REGISTRY }}/${{ env.NAMESPACE }}/${{ matrix.image }}
           subject-digest: ${{ steps.push.outputs.digest }}
           push-to-registry: true