github: rename and fix permissions

.github/workflows/dockerhub.yml → .github/workflows/packages.yml

@@ -1,12 +1,11 @@
 ---
-name: dockerhub
+name: github-packages
 
 on:
   push:
     branches:
       - '5.*'
-permissions:
-  contents: read # to fetch code (actions/checkout)
+
 jobs:
   pre-docker:
     runs-on: ubuntu-latest