Fix RHEL docker containers (#282)

* Fix RHEL docker containers

- avoid `yum update` since that can update the distro minor version

.github/workflows/containers.yml

@@ -6,6 +6,10 @@ on:
   workflow_dispatch:
   schedule:
     - cron: 0 5 * * *
+  push:
+    branches: [main]
+    paths:
+      - '.github/workflows/containers.yml'
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}