Return correct url for relative paths in messages (#75562)

changelogs/fragments/fix_relative_msg_urls.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - Since ansible/2.11 doc site was removed, the current relative messages point to a 404 url, this fixes it by chainging the target to ansible-core/2.11

lib/ansible/config/base.yml

@@ -1302,7 +1302,7 @@ DISPLAY_SKIPPED_HOSTS:
   type: boolean
 DOCSITE_ROOT_URL:
   name: Root docsite URL
-  default: https://docs.ansible.com/ansible/
+  default: https://docs.ansible.com/ansible-core/
   description: Root docsite URL used to generate docs URLs in warning/error text;
                must be an absolute URL with valid scheme and trailing slash.
   ini: