ITPLT-3984 variable precedence wasn't great, set a dedicated task to validate that marketplace is available

roles/product_install/tasks/main.yml

@@ -19,6 +19,12 @@
 
   when: cached.stat.exists
 
+- name: Confirm marketplace is available
+  ansible.builtin.uri:
+    url: "{{ atl_product_marketplace_url }}/healthcheck"
+    status_code: 200
+    return_content: no
+    http_agent: "ansible-httpget_{{ ansible_play_name }}"
 
 - name: Determine if requested version is 'latest'
   ansible.builtin.set_fact: