backup: Ensure colon are preserved in awx spec

Due to the way the command is run, the field with a colon in it will
generate a broken yaml serialization. This commit aims to keep it
accurate.

roles/backup/tasks/awx-cro.yml

@@ -21,4 +21,4 @@
     namespace: "{{ backup_pvc_namespace }}"
     pod: "{{ meta.name }}-db-management"
     command: >-
-      bash -c "echo '{{ awx_spec }}' > {{ backup_dir }}/awx_object"
+      bash -c 'echo "$0" > {{ backup_dir  }}/awx_object' {{ awx_spec | quote  }}