backup: add action.yml skeleton

backup/action.yml

@@ -0,0 +1,13 @@
+name: backup
+description: backup all postgres databases
+
+runs:
+  using: "composite"
+  steps:
+    - name: dump databases
+      shell: bash
+      run: |
+        docker ps
+
+    # - name: backup databases
+    #   run: |