Use env variable for docker image name

.github/workflows/trivy.yml

@@ -22,16 +22,20 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v4
 
+      - name: Set environment variables
+        run: |
+          echo IMAGE_NAME=$REGISTRY/$(echo ${GITHUB_REPOSITORY,,}) >> $GITHUB_ENV
+
       - name: Build image from Dockerfile
         run: |
-          docker build --build-arg VERSION=$GITHUB_RUN_NUMBER --build-arg REVISION=${{ github.sha }} -t ghcr.io/$GITHUB_REPOSITORY:${{ github.sha }} .
+          docker build --build-arg VERSION=$GITHUB_RUN_NUMBER --build-arg REVISION=${{ github.sha }} -t ${{ env.IMAGE_NAME }}:${{ github.sha }} .
 
       - name: Run Trivy vulnerability scanner
         uses: aquasecurity/trivy-action@7b7aa264d83dc58691451798b4d117d53d21edfe
         env:
           ACTIONS_RUNTIME_TOKEN: ${{ secrets.GITHUB_TOKEN }} # Addresses https://github.com/aquasecurity/trivy-action/issues/389
         with:
-          image-ref: 'ghcr.io/geowerkstatt/interlis-check-service:${{ github.sha }}'
+          image-ref: '${{ env.IMAGE_NAME }}:${{ github.sha }}'
           format: 'template'
           template: '@/contrib/sarif.tpl'
           output: 'trivy-results.sarif'