actions: separate trivy

.github/workflows/run_trivy.yml

@@ -1,4 +1,4 @@
-name: build and publish container
+name: scan container image
 
 on:
   workflow_run:
@@ -14,6 +14,7 @@ env:
 jobs:
   build:
     runs-on: ubuntu-latest
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
 
     steps:
       - uses: actions/checkout@v3