Fix n8n playbook dry-run failure on 1Password lookups

Shell tasks are skipped in check mode by default, leaving op_item.stdout
empty and breaking from_json in the set_fact. The op item get calls are
read-only, so mark them check_mode: no so dry runs reflect reality.

playbooks/n8n.yml

@@ -24,6 +24,7 @@
       register: op_check
       failed_when: false
       changed_when: false
+      check_mode: no
       environment:
         OP_SERVICE_ACCOUNT_TOKEN: "{{ lookup('env','OP_SERVICE_ACCOUNT_TOKEN') }}"
 
@@ -33,6 +34,7 @@
       shell: |
         op item get "{{ stack_name }}" --vault="Automation" --format json
       register: op_item
+      check_mode: no
       environment:
         OP_SERVICE_ACCOUNT_TOKEN: "{{ lookup('env','OP_SERVICE_ACCOUNT_TOKEN') }}"