add security permissions for security-scan job in DevContainer CI workflow

Author: lxsaah

.github/workflows/devcontainer.yml

@@ -153,6 +153,10 @@ jobs:
     runs-on: ubuntu-latest
     needs: build-devcontainer
     if: github.event_name != 'pull_request'
+    permissions:
+      contents: read
+      security-events: write
+      actions: read
 
     steps:
       - name: Checkout repository