jmri: fix xpra remove task idempotency (skip if already from upstream repo)

ansible/roles/jmri/tasks/main.yml

@@ -312,6 +312,7 @@
   ansible.builtin.apt:
     name: xpra
     state: absent
+  when: "'xpra' in ansible_facts.packages and ansible_facts.packages['xpra'][0].source != 'xpra.org'"
 
 - name: Install xpra.org apt signing key
   ansible.builtin.get_url: