modify run conditions for docker workflow

Author: LucaMarconato

.github/workflows/build_image.yml

@@ -14,7 +14,7 @@ concurrency:
 
 jobs:
     build:
-        if: ${{ github.event.workflow_run.conclusion == 'success' && startsWith(github.ref, 'refs/tags/v') }}
+        if: ${{ github.event_name == 'workflow_run' && github.event.workflow_run.conclusion == 'success' && startsWith(github.ref, 'refs/tags/v') || github.event_name == 'workflow_dispatch' }}
         runs-on: ubuntu-latest
 
         defaults: