Clarify that the license module requires fetching subs prior (ansible…

…#14351)

Co-authored-by: Pablo N. Hess <[email protected]>

awx_collection/plugins/modules/license.py

@@ -52,7 +52,12 @@
   license:
     manifest: "/tmp/my_manifest.zip"
 
-- name: Attach to a pool
+- name: Use the subscriptions module to fetch subscriptions from Red Hat or Red Hat Satellite
+  subscriptions:
+    username: "my_satellite_username"
+    password: "my_satellite_password"
+
+- name: Attach to a pool (requires fetching subscriptions at least once before)
   license:
     pool_id: 123456