Print a deprecation notice for postgres upgrades if <11

Closes #5095 (closed).

files/gitlab-cookbooks/package/libraries/omnibus_helper.rb

@@ -167,7 +167,7 @@ class OmnibusHelper # rubocop:disable Style/MultilineIfModifier (disabled so we
     gitlab_rb_config = Gitlab['node'].normal
 
     return unless gitlab_rb_config['gitlab']['postgresql']['version']
-    return if gitlab_rb_config['postgresql']['version'].split(".")[0].to_f >= '11'.to_f
+    return if gitlab_rb_config['gitlab']['postgresql']['version'].split(".")[0].to_f >= '11'.to_f
 
     LoggingHelper.warning(%q(
       === WARNING ===