test: pull image from opencode

Author: jan-abel-inwt

.github/workflows/test-opencode.yml

@@ -1,5 +1,8 @@
 name: probe-plain-alpine
-on: workflow_dispatch
+on:
+  workflow_dispatch:
+  push:
+    branches: ["test/gitlab-ci-with-opencode-images"]
 jobs:
   probe:
     runs-on: ubuntu-latest